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  <div class="section" id="s-postgresql-specific-model-fields">
<span id="postgresql-specific-model-fields"></span><h1>PostgreSQL specific model fields<a class="headerlink" href="#postgresql-specific-model-fields" title="Permalink to this headline">¶</a></h1>
<p>All of these fields are available from the <code class="docutils literal notranslate"><span class="pre">django.contrib.postgres.fields</span></code>
module.</p>
<div class="section" id="s-arrayfield">
<span id="arrayfield"></span><h2><code class="docutils literal notranslate"><span class="pre">ArrayField</span></code><a class="headerlink" href="#arrayfield" title="Permalink to this headline">¶</a></h2>
<dl class="class">
<dt id="django.contrib.postgres.fields.ArrayField">
<em class="property">class </em><code class="descname">ArrayField</code>(<em>base_field</em>, <em>size=None</em>, <em>**options</em>)<a class="reference internal" href="../../../_modules/django/contrib/postgres/fields/array.html#ArrayField"><span class="viewcode-link">[source]</span></a><a class="headerlink" href="#django.contrib.postgres.fields.ArrayField" title="Permalink to this definition">¶</a></dt>
<dd><p>A field for storing lists of data. Most field types can be used, you simply
pass another field instance as the <a class="reference internal" href="#django.contrib.postgres.fields.ArrayField.base_field" title="django.contrib.postgres.fields.ArrayField.base_field"><code class="xref py py-attr docutils literal notranslate"><span class="pre">base_field</span></code></a>. You may also specify a <a class="reference internal" href="#django.contrib.postgres.fields.ArrayField.size" title="django.contrib.postgres.fields.ArrayField.size"><code class="xref py py-attr docutils literal notranslate"><span class="pre">size</span></code></a>. <code class="docutils literal notranslate"><span class="pre">ArrayField</span></code> can be nested to store multi-dimensional
arrays.</p>
<p>If you give the field a <a class="reference internal" href="../../models/fields.html#django.db.models.Field.default" title="django.db.models.Field.default"><code class="xref py py-attr docutils literal notranslate"><span class="pre">default</span></code></a>, ensure
it’s a callable such as <code class="docutils literal notranslate"><span class="pre">list</span></code> (for an empty default) or a callable that
returns a list (such as a function). Incorrectly using <code class="docutils literal notranslate"><span class="pre">default=[]</span></code>
creates a mutable default that is shared between all instances of
<code class="docutils literal notranslate"><span class="pre">ArrayField</span></code>.</p>
<dl class="attribute">
<dt id="django.contrib.postgres.fields.ArrayField.base_field">
<code class="descname">base_field</code><a class="headerlink" href="#django.contrib.postgres.fields.ArrayField.base_field" title="Permalink to this definition">¶</a></dt>
<dd><p>This is a required argument.</p>
<p>Specifies the underlying data type and behavior for the array. It
should be an instance of a subclass of
<a class="reference internal" href="../../models/fields.html#django.db.models.Field" title="django.db.models.Field"><code class="xref py py-class docutils literal notranslate"><span class="pre">Field</span></code></a>. For example, it could be an
<a class="reference internal" href="../../models/fields.html#django.db.models.IntegerField" title="django.db.models.IntegerField"><code class="xref py py-class docutils literal notranslate"><span class="pre">IntegerField</span></code></a> or a
<a class="reference internal" href="../../models/fields.html#django.db.models.CharField" title="django.db.models.CharField"><code class="xref py py-class docutils literal notranslate"><span class="pre">CharField</span></code></a>. Most field types are permitted,
with the exception of those handling relational data
(<a class="reference internal" href="../../models/fields.html#django.db.models.ForeignKey" title="django.db.models.ForeignKey"><code class="xref py py-class docutils literal notranslate"><span class="pre">ForeignKey</span></code></a>,
<a class="reference internal" href="../../models/fields.html#django.db.models.OneToOneField" title="django.db.models.OneToOneField"><code class="xref py py-class docutils literal notranslate"><span class="pre">OneToOneField</span></code></a> and
<a class="reference internal" href="../../models/fields.html#django.db.models.ManyToManyField" title="django.db.models.ManyToManyField"><code class="xref py py-class docutils literal notranslate"><span class="pre">ManyToManyField</span></code></a>).</p>
<p>It is possible to nest array fields - you can specify an instance of
<code class="docutils literal notranslate"><span class="pre">ArrayField</span></code> as the <code class="docutils literal notranslate"><span class="pre">base_field</span></code>. For example:</p>
<div class="highlight-default notranslate"><div class="highlight"><pre><span></span><span class="kn">from</span> <span class="nn">django.db</span> <span class="k">import</span> <span class="n">models</span>
<span class="kn">from</span> <span class="nn">django.contrib.postgres.fields</span> <span class="k">import</span> <span class="n">ArrayField</span>

<span class="k">class</span> <span class="nc">ChessBoard</span><span class="p">(</span><span class="n">models</span><span class="o">.</span><span class="n">Model</span><span class="p">):</span>
    <span class="n">board</span> <span class="o">=</span> <span class="n">ArrayField</span><span class="p">(</span>
        <span class="n">ArrayField</span><span class="p">(</span>
            <span class="n">models</span><span class="o">.</span><span class="n">CharField</span><span class="p">(</span><span class="n">max_length</span><span class="o">=</span><span class="mi">10</span><span class="p">,</span> <span class="n">blank</span><span class="o">=</span><span class="kc">True</span><span class="p">),</span>
            <span class="n">size</span><span class="o">=</span><span class="mi">8</span><span class="p">,</span>
        <span class="p">),</span>
        <span class="n">size</span><span class="o">=</span><span class="mi">8</span><span class="p">,</span>
    <span class="p">)</span>
</pre></div>
</div>
<p>Transformation of values between the database and the model, validation
of data and configuration, and serialization are all delegated to the
underlying base field.</p>
</dd></dl>

<dl class="attribute">
<dt id="django.contrib.postgres.fields.ArrayField.size">
<code class="descname">size</code><a class="headerlink" href="#django.contrib.postgres.fields.ArrayField.size" title="Permalink to this definition">¶</a></dt>
<dd><p>This is an optional argument.</p>
<p>If passed, the array will have a maximum size as specified. This will
be passed to the database, although PostgreSQL at present does not
enforce the restriction.</p>
</dd></dl>

</dd></dl>

<div class="admonition note">
<p class="first admonition-title">Note</p>
<p>When nesting <code class="docutils literal notranslate"><span class="pre">ArrayField</span></code>, whether you use the <cite>size</cite> parameter or not,
PostgreSQL requires that the arrays are rectangular:</p>
<div class="highlight-default notranslate"><div class="highlight"><pre><span></span><span class="kn">from</span> <span class="nn">django.contrib.postgres.fields</span> <span class="k">import</span> <span class="n">ArrayField</span>
<span class="kn">from</span> <span class="nn">django.db</span> <span class="k">import</span> <span class="n">models</span>

<span class="k">class</span> <span class="nc">Board</span><span class="p">(</span><span class="n">models</span><span class="o">.</span><span class="n">Model</span><span class="p">):</span>
    <span class="n">pieces</span> <span class="o">=</span> <span class="n">ArrayField</span><span class="p">(</span><span class="n">ArrayField</span><span class="p">(</span><span class="n">models</span><span class="o">.</span><span class="n">IntegerField</span><span class="p">()))</span>

<span class="c1"># Valid</span>
<span class="n">Board</span><span class="p">(</span><span class="n">pieces</span><span class="o">=</span><span class="p">[</span>
    <span class="p">[</span><span class="mi">2</span><span class="p">,</span> <span class="mi">3</span><span class="p">],</span>
    <span class="p">[</span><span class="mi">2</span><span class="p">,</span> <span class="mi">1</span><span class="p">],</span>
<span class="p">])</span>

<span class="c1"># Not valid</span>
<span class="n">Board</span><span class="p">(</span><span class="n">pieces</span><span class="o">=</span><span class="p">[</span>
    <span class="p">[</span><span class="mi">2</span><span class="p">,</span> <span class="mi">3</span><span class="p">],</span>
    <span class="p">[</span><span class="mi">2</span><span class="p">],</span>
<span class="p">])</span>
</pre></div>
</div>
<p class="last">If irregular shapes are required, then the underlying field should be made
nullable and the values padded with <code class="docutils literal notranslate"><span class="pre">None</span></code>.</p>
</div>
<div class="section" id="s-querying-arrayfield">
<span id="querying-arrayfield"></span><h3>Querying <code class="docutils literal notranslate"><span class="pre">ArrayField</span></code><a class="headerlink" href="#querying-arrayfield" title="Permalink to this headline">¶</a></h3>
<p>There are a number of custom lookups and transforms for <a class="reference internal" href="#django.contrib.postgres.fields.ArrayField" title="django.contrib.postgres.fields.ArrayField"><code class="xref py py-class docutils literal notranslate"><span class="pre">ArrayField</span></code></a>.
We will use the following example model:</p>
<div class="highlight-default notranslate"><div class="highlight"><pre><span></span><span class="kn">from</span> <span class="nn">django.db</span> <span class="k">import</span> <span class="n">models</span>
<span class="kn">from</span> <span class="nn">django.contrib.postgres.fields</span> <span class="k">import</span> <span class="n">ArrayField</span>

<span class="k">class</span> <span class="nc">Post</span><span class="p">(</span><span class="n">models</span><span class="o">.</span><span class="n">Model</span><span class="p">):</span>
    <span class="n">name</span> <span class="o">=</span> <span class="n">models</span><span class="o">.</span><span class="n">CharField</span><span class="p">(</span><span class="n">max_length</span><span class="o">=</span><span class="mi">200</span><span class="p">)</span>
    <span class="n">tags</span> <span class="o">=</span> <span class="n">ArrayField</span><span class="p">(</span><span class="n">models</span><span class="o">.</span><span class="n">CharField</span><span class="p">(</span><span class="n">max_length</span><span class="o">=</span><span class="mi">200</span><span class="p">),</span> <span class="n">blank</span><span class="o">=</span><span class="kc">True</span><span class="p">)</span>

    <span class="k">def</span> <span class="nf">__str__</span><span class="p">(</span><span class="bp">self</span><span class="p">):</span>  <span class="c1"># __unicode__ on Python 2</span>
        <span class="k">return</span> <span class="bp">self</span><span class="o">.</span><span class="n">name</span>
</pre></div>
</div>
<div class="section" id="s-contains">
<span id="s-std:fieldlookup-arrayfield.contains"></span><span id="contains"></span><span id="std:fieldlookup-arrayfield.contains"></span><h4><code class="docutils literal notranslate"><span class="pre">contains</span></code><a class="headerlink" href="#contains" title="Permalink to this headline">¶</a></h4>
<p>The <a class="reference internal" href="../../models/querysets.html#std:fieldlookup-contains"><code class="xref std std-lookup docutils literal notranslate"><span class="pre">contains</span></code></a> lookup is overridden on <a class="reference internal" href="#django.contrib.postgres.fields.ArrayField" title="django.contrib.postgres.fields.ArrayField"><code class="xref py py-class docutils literal notranslate"><span class="pre">ArrayField</span></code></a>. The
returned objects will be those where the values passed are a subset of the
data. It uses the SQL operator <code class="docutils literal notranslate"><span class="pre">&#64;&gt;</span></code>. For example:</p>
<div class="highlight-default notranslate"><div class="highlight"><pre><span></span><span class="gp">&gt;&gt;&gt; </span><span class="n">Post</span><span class="o">.</span><span class="n">objects</span><span class="o">.</span><span class="n">create</span><span class="p">(</span><span class="n">name</span><span class="o">=</span><span class="s1">&#39;First post&#39;</span><span class="p">,</span> <span class="n">tags</span><span class="o">=</span><span class="p">[</span><span class="s1">&#39;thoughts&#39;</span><span class="p">,</span> <span class="s1">&#39;django&#39;</span><span class="p">])</span>
<span class="gp">&gt;&gt;&gt; </span><span class="n">Post</span><span class="o">.</span><span class="n">objects</span><span class="o">.</span><span class="n">create</span><span class="p">(</span><span class="n">name</span><span class="o">=</span><span class="s1">&#39;Second post&#39;</span><span class="p">,</span> <span class="n">tags</span><span class="o">=</span><span class="p">[</span><span class="s1">&#39;thoughts&#39;</span><span class="p">])</span>
<span class="gp">&gt;&gt;&gt; </span><span class="n">Post</span><span class="o">.</span><span class="n">objects</span><span class="o">.</span><span class="n">create</span><span class="p">(</span><span class="n">name</span><span class="o">=</span><span class="s1">&#39;Third post&#39;</span><span class="p">,</span> <span class="n">tags</span><span class="o">=</span><span class="p">[</span><span class="s1">&#39;tutorial&#39;</span><span class="p">,</span> <span class="s1">&#39;django&#39;</span><span class="p">])</span>

<span class="gp">&gt;&gt;&gt; </span><span class="n">Post</span><span class="o">.</span><span class="n">objects</span><span class="o">.</span><span class="n">filter</span><span class="p">(</span><span class="n">tags__contains</span><span class="o">=</span><span class="p">[</span><span class="s1">&#39;thoughts&#39;</span><span class="p">])</span>
<span class="go">&lt;QuerySet [&lt;Post: First post&gt;, &lt;Post: Second post&gt;]&gt;</span>

<span class="gp">&gt;&gt;&gt; </span><span class="n">Post</span><span class="o">.</span><span class="n">objects</span><span class="o">.</span><span class="n">filter</span><span class="p">(</span><span class="n">tags__contains</span><span class="o">=</span><span class="p">[</span><span class="s1">&#39;django&#39;</span><span class="p">])</span>
<span class="go">&lt;QuerySet [&lt;Post: First post&gt;, &lt;Post: Third post&gt;]&gt;</span>

<span class="gp">&gt;&gt;&gt; </span><span class="n">Post</span><span class="o">.</span><span class="n">objects</span><span class="o">.</span><span class="n">filter</span><span class="p">(</span><span class="n">tags__contains</span><span class="o">=</span><span class="p">[</span><span class="s1">&#39;django&#39;</span><span class="p">,</span> <span class="s1">&#39;thoughts&#39;</span><span class="p">])</span>
<span class="go">&lt;QuerySet [&lt;Post: First post&gt;]&gt;</span>
</pre></div>
</div>
</div>
<div class="section" id="s-contained-by">
<span id="s-std:fieldlookup-arrayfield.contained_by"></span><span id="contained-by"></span><span id="std:fieldlookup-arrayfield.contained_by"></span><h4><code class="docutils literal notranslate"><span class="pre">contained_by</span></code><a class="headerlink" href="#contained-by" title="Permalink to this headline">¶</a></h4>
<p>This is the inverse of the <a class="reference internal" href="#std:fieldlookup-arrayfield.contains"><code class="xref std std-lookup docutils literal notranslate"><span class="pre">contains</span></code></a> lookup -
the objects returned will be those where the data is a subset of the values
passed. It uses the SQL operator <code class="docutils literal notranslate"><span class="pre">&lt;&#64;</span></code>. For example:</p>
<div class="highlight-default notranslate"><div class="highlight"><pre><span></span><span class="gp">&gt;&gt;&gt; </span><span class="n">Post</span><span class="o">.</span><span class="n">objects</span><span class="o">.</span><span class="n">create</span><span class="p">(</span><span class="n">name</span><span class="o">=</span><span class="s1">&#39;First post&#39;</span><span class="p">,</span> <span class="n">tags</span><span class="o">=</span><span class="p">[</span><span class="s1">&#39;thoughts&#39;</span><span class="p">,</span> <span class="s1">&#39;django&#39;</span><span class="p">])</span>
<span class="gp">&gt;&gt;&gt; </span><span class="n">Post</span><span class="o">.</span><span class="n">objects</span><span class="o">.</span><span class="n">create</span><span class="p">(</span><span class="n">name</span><span class="o">=</span><span class="s1">&#39;Second post&#39;</span><span class="p">,</span> <span class="n">tags</span><span class="o">=</span><span class="p">[</span><span class="s1">&#39;thoughts&#39;</span><span class="p">])</span>
<span class="gp">&gt;&gt;&gt; </span><span class="n">Post</span><span class="o">.</span><span class="n">objects</span><span class="o">.</span><span class="n">create</span><span class="p">(</span><span class="n">name</span><span class="o">=</span><span class="s1">&#39;Third post&#39;</span><span class="p">,</span> <span class="n">tags</span><span class="o">=</span><span class="p">[</span><span class="s1">&#39;tutorial&#39;</span><span class="p">,</span> <span class="s1">&#39;django&#39;</span><span class="p">])</span>

<span class="gp">&gt;&gt;&gt; </span><span class="n">Post</span><span class="o">.</span><span class="n">objects</span><span class="o">.</span><span class="n">filter</span><span class="p">(</span><span class="n">tags__contained_by</span><span class="o">=</span><span class="p">[</span><span class="s1">&#39;thoughts&#39;</span><span class="p">,</span> <span class="s1">&#39;django&#39;</span><span class="p">])</span>
<span class="go">&lt;QuerySet [&lt;Post: First post&gt;, &lt;Post: Second post&gt;]&gt;</span>

<span class="gp">&gt;&gt;&gt; </span><span class="n">Post</span><span class="o">.</span><span class="n">objects</span><span class="o">.</span><span class="n">filter</span><span class="p">(</span><span class="n">tags__contained_by</span><span class="o">=</span><span class="p">[</span><span class="s1">&#39;thoughts&#39;</span><span class="p">,</span> <span class="s1">&#39;django&#39;</span><span class="p">,</span> <span class="s1">&#39;tutorial&#39;</span><span class="p">])</span>
<span class="go">&lt;QuerySet [&lt;Post: First post&gt;, &lt;Post: Second post&gt;, &lt;Post: Third post&gt;]&gt;</span>
</pre></div>
</div>
</div>
<div class="section" id="s-overlap">
<span id="s-std:fieldlookup-arrayfield.overlap"></span><span id="overlap"></span><span id="std:fieldlookup-arrayfield.overlap"></span><h4><code class="docutils literal notranslate"><span class="pre">overlap</span></code><a class="headerlink" href="#overlap" title="Permalink to this headline">¶</a></h4>
<p>Returns objects where the data shares any results with the values passed. Uses
the SQL operator <code class="docutils literal notranslate"><span class="pre">&amp;&amp;</span></code>. For example:</p>
<div class="highlight-default notranslate"><div class="highlight"><pre><span></span><span class="gp">&gt;&gt;&gt; </span><span class="n">Post</span><span class="o">.</span><span class="n">objects</span><span class="o">.</span><span class="n">create</span><span class="p">(</span><span class="n">name</span><span class="o">=</span><span class="s1">&#39;First post&#39;</span><span class="p">,</span> <span class="n">tags</span><span class="o">=</span><span class="p">[</span><span class="s1">&#39;thoughts&#39;</span><span class="p">,</span> <span class="s1">&#39;django&#39;</span><span class="p">])</span>
<span class="gp">&gt;&gt;&gt; </span><span class="n">Post</span><span class="o">.</span><span class="n">objects</span><span class="o">.</span><span class="n">create</span><span class="p">(</span><span class="n">name</span><span class="o">=</span><span class="s1">&#39;Second post&#39;</span><span class="p">,</span> <span class="n">tags</span><span class="o">=</span><span class="p">[</span><span class="s1">&#39;thoughts&#39;</span><span class="p">])</span>
<span class="gp">&gt;&gt;&gt; </span><span class="n">Post</span><span class="o">.</span><span class="n">objects</span><span class="o">.</span><span class="n">create</span><span class="p">(</span><span class="n">name</span><span class="o">=</span><span class="s1">&#39;Third post&#39;</span><span class="p">,</span> <span class="n">tags</span><span class="o">=</span><span class="p">[</span><span class="s1">&#39;tutorial&#39;</span><span class="p">,</span> <span class="s1">&#39;django&#39;</span><span class="p">])</span>

<span class="gp">&gt;&gt;&gt; </span><span class="n">Post</span><span class="o">.</span><span class="n">objects</span><span class="o">.</span><span class="n">filter</span><span class="p">(</span><span class="n">tags__overlap</span><span class="o">=</span><span class="p">[</span><span class="s1">&#39;thoughts&#39;</span><span class="p">])</span>
<span class="go">&lt;QuerySet [&lt;Post: First post&gt;, &lt;Post: Second post&gt;]&gt;</span>

<span class="gp">&gt;&gt;&gt; </span><span class="n">Post</span><span class="o">.</span><span class="n">objects</span><span class="o">.</span><span class="n">filter</span><span class="p">(</span><span class="n">tags__overlap</span><span class="o">=</span><span class="p">[</span><span class="s1">&#39;thoughts&#39;</span><span class="p">,</span> <span class="s1">&#39;tutorial&#39;</span><span class="p">])</span>
<span class="go">&lt;QuerySet [&lt;Post: First post&gt;, &lt;Post: Second post&gt;, &lt;Post: Third post&gt;]&gt;</span>
</pre></div>
</div>
</div>
<div class="section" id="s-len">
<span id="s-std:fieldlookup-arrayfield.len"></span><span id="len"></span><span id="std:fieldlookup-arrayfield.len"></span><h4><code class="docutils literal notranslate"><span class="pre">len</span></code><a class="headerlink" href="#len" title="Permalink to this headline">¶</a></h4>
<p>Returns the length of the array. The lookups available afterwards are those
available for <a class="reference internal" href="../../models/fields.html#django.db.models.IntegerField" title="django.db.models.IntegerField"><code class="xref py py-class docutils literal notranslate"><span class="pre">IntegerField</span></code></a>. For example:</p>
<div class="highlight-default notranslate"><div class="highlight"><pre><span></span><span class="gp">&gt;&gt;&gt; </span><span class="n">Post</span><span class="o">.</span><span class="n">objects</span><span class="o">.</span><span class="n">create</span><span class="p">(</span><span class="n">name</span><span class="o">=</span><span class="s1">&#39;First post&#39;</span><span class="p">,</span> <span class="n">tags</span><span class="o">=</span><span class="p">[</span><span class="s1">&#39;thoughts&#39;</span><span class="p">,</span> <span class="s1">&#39;django&#39;</span><span class="p">])</span>
<span class="gp">&gt;&gt;&gt; </span><span class="n">Post</span><span class="o">.</span><span class="n">objects</span><span class="o">.</span><span class="n">create</span><span class="p">(</span><span class="n">name</span><span class="o">=</span><span class="s1">&#39;Second post&#39;</span><span class="p">,</span> <span class="n">tags</span><span class="o">=</span><span class="p">[</span><span class="s1">&#39;thoughts&#39;</span><span class="p">])</span>

<span class="gp">&gt;&gt;&gt; </span><span class="n">Post</span><span class="o">.</span><span class="n">objects</span><span class="o">.</span><span class="n">filter</span><span class="p">(</span><span class="n">tags__len</span><span class="o">=</span><span class="mi">1</span><span class="p">)</span>
<span class="go">&lt;QuerySet [&lt;Post: Second post&gt;]&gt;</span>
</pre></div>
</div>
</div>
<div class="section" id="s-index-transforms">
<span id="s-std:fieldlookup-arrayfield.index"></span><span id="index-transforms"></span><span id="std:fieldlookup-arrayfield.index"></span><h4>Index transforms<a class="headerlink" href="#index-transforms" title="Permalink to this headline">¶</a></h4>
<p>This class of transforms allows you to index into the array in queries. Any
non-negative integer can be used. There are no errors if it exceeds the
<a class="reference internal" href="#django.contrib.postgres.fields.ArrayField.size" title="django.contrib.postgres.fields.ArrayField.size"><code class="xref py py-attr docutils literal notranslate"><span class="pre">size</span></code></a> of the array. The lookups available after the
transform are those from the <a class="reference internal" href="#django.contrib.postgres.fields.ArrayField.base_field" title="django.contrib.postgres.fields.ArrayField.base_field"><code class="xref py py-attr docutils literal notranslate"><span class="pre">base_field</span></code></a>. For
example:</p>
<div class="highlight-default notranslate"><div class="highlight"><pre><span></span><span class="gp">&gt;&gt;&gt; </span><span class="n">Post</span><span class="o">.</span><span class="n">objects</span><span class="o">.</span><span class="n">create</span><span class="p">(</span><span class="n">name</span><span class="o">=</span><span class="s1">&#39;First post&#39;</span><span class="p">,</span> <span class="n">tags</span><span class="o">=</span><span class="p">[</span><span class="s1">&#39;thoughts&#39;</span><span class="p">,</span> <span class="s1">&#39;django&#39;</span><span class="p">])</span>
<span class="gp">&gt;&gt;&gt; </span><span class="n">Post</span><span class="o">.</span><span class="n">objects</span><span class="o">.</span><span class="n">create</span><span class="p">(</span><span class="n">name</span><span class="o">=</span><span class="s1">&#39;Second post&#39;</span><span class="p">,</span> <span class="n">tags</span><span class="o">=</span><span class="p">[</span><span class="s1">&#39;thoughts&#39;</span><span class="p">])</span>

<span class="gp">&gt;&gt;&gt; </span><span class="n">Post</span><span class="o">.</span><span class="n">objects</span><span class="o">.</span><span class="n">filter</span><span class="p">(</span><span class="n">tags__0</span><span class="o">=</span><span class="s1">&#39;thoughts&#39;</span><span class="p">)</span>
<span class="go">&lt;QuerySet [&lt;Post: First post&gt;, &lt;Post: Second post&gt;]&gt;</span>

<span class="gp">&gt;&gt;&gt; </span><span class="n">Post</span><span class="o">.</span><span class="n">objects</span><span class="o">.</span><span class="n">filter</span><span class="p">(</span><span class="n">tags__1__iexact</span><span class="o">=</span><span class="s1">&#39;Django&#39;</span><span class="p">)</span>
<span class="go">&lt;QuerySet [&lt;Post: First post&gt;]&gt;</span>

<span class="gp">&gt;&gt;&gt; </span><span class="n">Post</span><span class="o">.</span><span class="n">objects</span><span class="o">.</span><span class="n">filter</span><span class="p">(</span><span class="n">tags__276</span><span class="o">=</span><span class="s1">&#39;javascript&#39;</span><span class="p">)</span>
<span class="go">&lt;QuerySet []&gt;</span>
</pre></div>
</div>
<div class="admonition note">
<p class="first admonition-title">Note</p>
<p class="last">PostgreSQL uses 1-based indexing for array fields when writing raw SQL.
However these indexes and those used in <a class="reference internal" href="#std:fieldlookup-arrayfield.slice"><code class="xref std std-lookup docutils literal notranslate"><span class="pre">slices</span></code></a>
use 0-based indexing to be consistent with Python.</p>
</div>
</div>
<div class="section" id="s-slice-transforms">
<span id="s-std:fieldlookup-arrayfield.slice"></span><span id="slice-transforms"></span><span id="std:fieldlookup-arrayfield.slice"></span><h4>Slice transforms<a class="headerlink" href="#slice-transforms" title="Permalink to this headline">¶</a></h4>
<p>This class of transforms allow you to take a slice of the array. Any two
non-negative integers can be used, separated by a single underscore. The
lookups available after the transform do not change. For example:</p>
<div class="highlight-default notranslate"><div class="highlight"><pre><span></span><span class="gp">&gt;&gt;&gt; </span><span class="n">Post</span><span class="o">.</span><span class="n">objects</span><span class="o">.</span><span class="n">create</span><span class="p">(</span><span class="n">name</span><span class="o">=</span><span class="s1">&#39;First post&#39;</span><span class="p">,</span> <span class="n">tags</span><span class="o">=</span><span class="p">[</span><span class="s1">&#39;thoughts&#39;</span><span class="p">,</span> <span class="s1">&#39;django&#39;</span><span class="p">])</span>
<span class="gp">&gt;&gt;&gt; </span><span class="n">Post</span><span class="o">.</span><span class="n">objects</span><span class="o">.</span><span class="n">create</span><span class="p">(</span><span class="n">name</span><span class="o">=</span><span class="s1">&#39;Second post&#39;</span><span class="p">,</span> <span class="n">tags</span><span class="o">=</span><span class="p">[</span><span class="s1">&#39;thoughts&#39;</span><span class="p">])</span>
<span class="gp">&gt;&gt;&gt; </span><span class="n">Post</span><span class="o">.</span><span class="n">objects</span><span class="o">.</span><span class="n">create</span><span class="p">(</span><span class="n">name</span><span class="o">=</span><span class="s1">&#39;Third post&#39;</span><span class="p">,</span> <span class="n">tags</span><span class="o">=</span><span class="p">[</span><span class="s1">&#39;django&#39;</span><span class="p">,</span> <span class="s1">&#39;python&#39;</span><span class="p">,</span> <span class="s1">&#39;thoughts&#39;</span><span class="p">])</span>

<span class="gp">&gt;&gt;&gt; </span><span class="n">Post</span><span class="o">.</span><span class="n">objects</span><span class="o">.</span><span class="n">filter</span><span class="p">(</span><span class="n">tags__0_1</span><span class="o">=</span><span class="p">[</span><span class="s1">&#39;thoughts&#39;</span><span class="p">])</span>
<span class="go">&lt;QuerySet [&lt;Post: First post&gt;, &lt;Post: Second post&gt;]&gt;</span>

<span class="gp">&gt;&gt;&gt; </span><span class="n">Post</span><span class="o">.</span><span class="n">objects</span><span class="o">.</span><span class="n">filter</span><span class="p">(</span><span class="n">tags__0_2__contains</span><span class="o">=</span><span class="p">[</span><span class="s1">&#39;thoughts&#39;</span><span class="p">])</span>
<span class="go">&lt;QuerySet [&lt;Post: First post&gt;, &lt;Post: Second post&gt;]&gt;</span>
</pre></div>
</div>
<div class="admonition note">
<p class="first admonition-title">Note</p>
<p class="last">PostgreSQL uses 1-based indexing for array fields when writing raw SQL.
However these slices and those used in <a class="reference internal" href="#std:fieldlookup-arrayfield.index"><code class="xref std std-lookup docutils literal notranslate"><span class="pre">indexes</span></code></a>
use 0-based indexing to be consistent with Python.</p>
</div>
<div class="admonition-multidimensional-arrays-with-indexes-and-slices admonition">
<p class="first admonition-title">Multidimensional arrays with indexes and slices</p>
<p class="last">PostgreSQL has some rather esoteric behavior when using indexes and slices
on multidimensional arrays. It will always work to use indexes to reach
down to the final underlying data, but most other slices behave strangely
at the database level and cannot be supported in a logical, consistent
fashion by Django.</p>
</div>
</div>
</div>
<div class="section" id="s-indexing-arrayfield">
<span id="indexing-arrayfield"></span><h3>Indexing <code class="docutils literal notranslate"><span class="pre">ArrayField</span></code><a class="headerlink" href="#indexing-arrayfield" title="Permalink to this headline">¶</a></h3>
<p>At present using <a class="reference internal" href="../../models/fields.html#django.db.models.Field.db_index" title="django.db.models.Field.db_index"><code class="xref py py-attr docutils literal notranslate"><span class="pre">db_index</span></code></a> will create a
<code class="docutils literal notranslate"><span class="pre">btree</span></code> index. This does not offer particularly significant help to querying.
A more useful index is a <code class="docutils literal notranslate"><span class="pre">GIN</span></code> index, which you should create using a
<a class="reference internal" href="../../migration-operations.html#django.db.migrations.operations.RunSQL" title="django.db.migrations.operations.RunSQL"><code class="xref py py-class docutils literal notranslate"><span class="pre">RunSQL</span></code></a> operation.</p>
</div>
</div>
<div class="section" id="s-citext-fields">
<span id="citext-fields"></span><h2><code class="docutils literal notranslate"><span class="pre">CIText</span></code> fields<a class="headerlink" href="#citext-fields" title="Permalink to this headline">¶</a></h2>
<dl class="class">
<dt id="django.contrib.postgres.fields.CIText">
<em class="property">class </em><code class="descname">CIText</code>(<em>**options</em>)<a class="reference internal" href="../../../_modules/django/contrib/postgres/fields/citext.html#CIText"><span class="viewcode-link">[source]</span></a><a class="headerlink" href="#django.contrib.postgres.fields.CIText" title="Permalink to this definition">¶</a></dt>
<dd><div class="versionadded">
<span class="title">New in Django 1.11.</span> </div>
<p>A mixin to create case-insensitive text fields backed by the <a class="reference external" href="https://www.postgresql.org/docs/current/static/citext.html">citext</a> type.
Read about <a class="reference external" href="https://www.postgresql.org/docs/current/static/citext.html#AEN178177">the performance considerations</a> prior to using it.</p>
<p>To use <code class="docutils literal notranslate"><span class="pre">citext</span></code>, use the <a class="reference internal" href="operations.html#django.contrib.postgres.operations.CITextExtension" title="django.contrib.postgres.operations.CITextExtension"><code class="xref py py-class docutils literal notranslate"><span class="pre">CITextExtension</span></code></a> operation to
<a class="reference internal" href="operations.html#create-postgresql-extensions"><span class="std std-ref">setup the citext extension</span></a> in
PostgreSQL before the first <code class="docutils literal notranslate"><span class="pre">CreateModel</span></code> migration operation.</p>
<p>Several fields that use the mixin are provided:</p>
</dd></dl>

<dl class="class">
<dt id="django.contrib.postgres.fields.CICharField">
<em class="property">class </em><code class="descname">CICharField</code>(<em>**options</em>)<a class="reference internal" href="../../../_modules/django/contrib/postgres/fields/citext.html#CICharField"><span class="viewcode-link">[source]</span></a><a class="headerlink" href="#django.contrib.postgres.fields.CICharField" title="Permalink to this definition">¶</a></dt>
<dd></dd></dl>

<dl class="class">
<dt id="django.contrib.postgres.fields.CIEmailField">
<em class="property">class </em><code class="descname">CIEmailField</code>(<em>**options</em>)<a class="reference internal" href="../../../_modules/django/contrib/postgres/fields/citext.html#CIEmailField"><span class="viewcode-link">[source]</span></a><a class="headerlink" href="#django.contrib.postgres.fields.CIEmailField" title="Permalink to this definition">¶</a></dt>
<dd></dd></dl>

<dl class="class">
<dt id="django.contrib.postgres.fields.CITextField">
<em class="property">class </em><code class="descname">CITextField</code>(<em>**options</em>)<a class="reference internal" href="../../../_modules/django/contrib/postgres/fields/citext.html#CITextField"><span class="viewcode-link">[source]</span></a><a class="headerlink" href="#django.contrib.postgres.fields.CITextField" title="Permalink to this definition">¶</a></dt>
<dd><p>These fields subclass <a class="reference internal" href="../../models/fields.html#django.db.models.CharField" title="django.db.models.CharField"><code class="xref py py-class docutils literal notranslate"><span class="pre">CharField</span></code></a>,
<a class="reference internal" href="../../models/fields.html#django.db.models.EmailField" title="django.db.models.EmailField"><code class="xref py py-class docutils literal notranslate"><span class="pre">EmailField</span></code></a>, and
<a class="reference internal" href="../../models/fields.html#django.db.models.TextField" title="django.db.models.TextField"><code class="xref py py-class docutils literal notranslate"><span class="pre">TextField</span></code></a>, respectively.</p>
<p><code class="docutils literal notranslate"><span class="pre">max_length</span></code> won’t be enforced in the database since <code class="docutils literal notranslate"><span class="pre">citext</span></code> behaves
similar to PostgreSQL’s <code class="docutils literal notranslate"><span class="pre">text</span></code> type.</p>
</dd></dl>

</div>
<div class="section" id="s-hstorefield">
<span id="hstorefield"></span><h2><code class="docutils literal notranslate"><span class="pre">HStoreField</span></code><a class="headerlink" href="#hstorefield" title="Permalink to this headline">¶</a></h2>
<dl class="class">
<dt id="django.contrib.postgres.fields.HStoreField">
<em class="property">class </em><code class="descname">HStoreField</code>(<em>**options</em>)<a class="reference internal" href="../../../_modules/django/contrib/postgres/fields/hstore.html#HStoreField"><span class="viewcode-link">[source]</span></a><a class="headerlink" href="#django.contrib.postgres.fields.HStoreField" title="Permalink to this definition">¶</a></dt>
<dd><p>A field for storing key-value pairs. The Python data type used is a
<code class="docutils literal notranslate"><span class="pre">dict</span></code>. Keys must be strings, and values may be either strings or nulls
(<code class="docutils literal notranslate"><span class="pre">None</span></code> in Python).</p>
<p>To use this field, you’ll need to:</p>
<ol class="arabic simple">
<li>Add <code class="docutils literal notranslate"><span class="pre">'django.contrib.postgres'</span></code> in your <a class="reference internal" href="../../settings.html#std:setting-INSTALLED_APPS"><code class="xref std std-setting docutils literal notranslate"><span class="pre">INSTALLED_APPS</span></code></a>.</li>
<li><a class="reference internal" href="operations.html#create-postgresql-extensions"><span class="std std-ref">Setup the hstore extension</span></a> in
PostgreSQL.</li>
</ol>
<p>You’ll see an error like <code class="docutils literal notranslate"><span class="pre">can't</span> <span class="pre">adapt</span> <span class="pre">type</span> <span class="pre">'dict'</span></code> if you skip the first
step, or <code class="docutils literal notranslate"><span class="pre">type</span> <span class="pre">&quot;hstore&quot;</span> <span class="pre">does</span> <span class="pre">not</span> <span class="pre">exist</span></code> if you skip the second.</p>
<div class="versionchanged">
<span class="title">Changed in Django 1.11:</span> <p>Added the ability to store nulls. Previously, they were cast to strings.</p>
</div>
</dd></dl>

<div class="admonition note">
<p class="first admonition-title">Note</p>
<p class="last">On occasions it may be useful to require or restrict the keys which are
valid for a given field. This can be done using the
<a class="reference internal" href="validators.html#django.contrib.postgres.validators.KeysValidator" title="django.contrib.postgres.validators.KeysValidator"><code class="xref py py-class docutils literal notranslate"><span class="pre">KeysValidator</span></code></a>.</p>
</div>
<div class="section" id="s-querying-hstorefield">
<span id="querying-hstorefield"></span><h3>Querying <code class="docutils literal notranslate"><span class="pre">HStoreField</span></code><a class="headerlink" href="#querying-hstorefield" title="Permalink to this headline">¶</a></h3>
<p>In addition to the ability to query by key, there are a number of custom
lookups available for <code class="docutils literal notranslate"><span class="pre">HStoreField</span></code>.</p>
<p>We will use the following example model:</p>
<div class="highlight-default notranslate"><div class="highlight"><pre><span></span><span class="kn">from</span> <span class="nn">django.contrib.postgres.fields</span> <span class="k">import</span> <span class="n">HStoreField</span>
<span class="kn">from</span> <span class="nn">django.db</span> <span class="k">import</span> <span class="n">models</span>

<span class="k">class</span> <span class="nc">Dog</span><span class="p">(</span><span class="n">models</span><span class="o">.</span><span class="n">Model</span><span class="p">):</span>
    <span class="n">name</span> <span class="o">=</span> <span class="n">models</span><span class="o">.</span><span class="n">CharField</span><span class="p">(</span><span class="n">max_length</span><span class="o">=</span><span class="mi">200</span><span class="p">)</span>
    <span class="n">data</span> <span class="o">=</span> <span class="n">HStoreField</span><span class="p">()</span>

    <span class="k">def</span> <span class="nf">__str__</span><span class="p">(</span><span class="bp">self</span><span class="p">):</span>  <span class="c1"># __unicode__ on Python 2</span>
        <span class="k">return</span> <span class="bp">self</span><span class="o">.</span><span class="n">name</span>
</pre></div>
</div>
<div class="section" id="s-key-lookups">
<span id="s-std:fieldlookup-hstorefield.key"></span><span id="key-lookups"></span><span id="std:fieldlookup-hstorefield.key"></span><h4>Key lookups<a class="headerlink" href="#key-lookups" title="Permalink to this headline">¶</a></h4>
<p>To query based on a given key, you simply use that key as the lookup name:</p>
<div class="highlight-default notranslate"><div class="highlight"><pre><span></span><span class="gp">&gt;&gt;&gt; </span><span class="n">Dog</span><span class="o">.</span><span class="n">objects</span><span class="o">.</span><span class="n">create</span><span class="p">(</span><span class="n">name</span><span class="o">=</span><span class="s1">&#39;Rufus&#39;</span><span class="p">,</span> <span class="n">data</span><span class="o">=</span><span class="p">{</span><span class="s1">&#39;breed&#39;</span><span class="p">:</span> <span class="s1">&#39;labrador&#39;</span><span class="p">})</span>
<span class="gp">&gt;&gt;&gt; </span><span class="n">Dog</span><span class="o">.</span><span class="n">objects</span><span class="o">.</span><span class="n">create</span><span class="p">(</span><span class="n">name</span><span class="o">=</span><span class="s1">&#39;Meg&#39;</span><span class="p">,</span> <span class="n">data</span><span class="o">=</span><span class="p">{</span><span class="s1">&#39;breed&#39;</span><span class="p">:</span> <span class="s1">&#39;collie&#39;</span><span class="p">})</span>

<span class="gp">&gt;&gt;&gt; </span><span class="n">Dog</span><span class="o">.</span><span class="n">objects</span><span class="o">.</span><span class="n">filter</span><span class="p">(</span><span class="n">data__breed</span><span class="o">=</span><span class="s1">&#39;collie&#39;</span><span class="p">)</span>
<span class="go">&lt;QuerySet [&lt;Dog: Meg&gt;]&gt;</span>
</pre></div>
</div>
<p>You can chain other lookups after key lookups:</p>
<div class="highlight-default notranslate"><div class="highlight"><pre><span></span><span class="gp">&gt;&gt;&gt; </span><span class="n">Dog</span><span class="o">.</span><span class="n">objects</span><span class="o">.</span><span class="n">filter</span><span class="p">(</span><span class="n">data__breed__contains</span><span class="o">=</span><span class="s1">&#39;l&#39;</span><span class="p">)</span>
<span class="go">&lt;QuerySet [&lt;Dog: Rufus&gt;, &lt;Dog: Meg&gt;]&gt;</span>
</pre></div>
</div>
<p>If the key you wish to query by clashes with the name of another lookup, you
need to use the <a class="reference internal" href="#std:fieldlookup-hstorefield.contains"><code class="xref std std-lookup docutils literal notranslate"><span class="pre">hstorefield.contains</span></code></a> lookup instead.</p>
<div class="admonition warning">
<p class="first admonition-title">Warning</p>
<p class="last">Since any string could be a key in a hstore value, any lookup other than
those listed below will be interpreted as a key lookup. No errors are
raised. Be extra careful for typing mistakes, and always check your queries
work as you intend.</p>
</div>
</div>
<div class="section" id="s-std:fieldlookup-hstorefield.contains">
<span id="s-id1"></span><span id="std:fieldlookup-hstorefield.contains"></span><span id="id1"></span><h4><code class="docutils literal notranslate"><span class="pre">contains</span></code><a class="headerlink" href="#std:fieldlookup-hstorefield.contains" title="Permalink to this headline">¶</a></h4>
<p>The <a class="reference internal" href="../../models/querysets.html#std:fieldlookup-contains"><code class="xref std std-lookup docutils literal notranslate"><span class="pre">contains</span></code></a> lookup is overridden on
<a class="reference internal" href="#django.contrib.postgres.fields.HStoreField" title="django.contrib.postgres.fields.HStoreField"><code class="xref py py-class docutils literal notranslate"><span class="pre">HStoreField</span></code></a>. The returned objects are
those where the given <code class="docutils literal notranslate"><span class="pre">dict</span></code> of key-value pairs are all contained in the
field. It uses the SQL operator <code class="docutils literal notranslate"><span class="pre">&#64;&gt;</span></code>. For example:</p>
<div class="highlight-default notranslate"><div class="highlight"><pre><span></span><span class="gp">&gt;&gt;&gt; </span><span class="n">Dog</span><span class="o">.</span><span class="n">objects</span><span class="o">.</span><span class="n">create</span><span class="p">(</span><span class="n">name</span><span class="o">=</span><span class="s1">&#39;Rufus&#39;</span><span class="p">,</span> <span class="n">data</span><span class="o">=</span><span class="p">{</span><span class="s1">&#39;breed&#39;</span><span class="p">:</span> <span class="s1">&#39;labrador&#39;</span><span class="p">,</span> <span class="s1">&#39;owner&#39;</span><span class="p">:</span> <span class="s1">&#39;Bob&#39;</span><span class="p">})</span>
<span class="gp">&gt;&gt;&gt; </span><span class="n">Dog</span><span class="o">.</span><span class="n">objects</span><span class="o">.</span><span class="n">create</span><span class="p">(</span><span class="n">name</span><span class="o">=</span><span class="s1">&#39;Meg&#39;</span><span class="p">,</span> <span class="n">data</span><span class="o">=</span><span class="p">{</span><span class="s1">&#39;breed&#39;</span><span class="p">:</span> <span class="s1">&#39;collie&#39;</span><span class="p">,</span> <span class="s1">&#39;owner&#39;</span><span class="p">:</span> <span class="s1">&#39;Bob&#39;</span><span class="p">})</span>
<span class="gp">&gt;&gt;&gt; </span><span class="n">Dog</span><span class="o">.</span><span class="n">objects</span><span class="o">.</span><span class="n">create</span><span class="p">(</span><span class="n">name</span><span class="o">=</span><span class="s1">&#39;Fred&#39;</span><span class="p">,</span> <span class="n">data</span><span class="o">=</span><span class="p">{})</span>

<span class="gp">&gt;&gt;&gt; </span><span class="n">Dog</span><span class="o">.</span><span class="n">objects</span><span class="o">.</span><span class="n">filter</span><span class="p">(</span><span class="n">data__contains</span><span class="o">=</span><span class="p">{</span><span class="s1">&#39;owner&#39;</span><span class="p">:</span> <span class="s1">&#39;Bob&#39;</span><span class="p">})</span>
<span class="go">&lt;QuerySet [&lt;Dog: Rufus&gt;, &lt;Dog: Meg&gt;]&gt;</span>

<span class="gp">&gt;&gt;&gt; </span><span class="n">Dog</span><span class="o">.</span><span class="n">objects</span><span class="o">.</span><span class="n">filter</span><span class="p">(</span><span class="n">data__contains</span><span class="o">=</span><span class="p">{</span><span class="s1">&#39;breed&#39;</span><span class="p">:</span> <span class="s1">&#39;collie&#39;</span><span class="p">})</span>
<span class="go">&lt;QuerySet [&lt;Dog: Meg&gt;]&gt;</span>
</pre></div>
</div>
</div>
<div class="section" id="s-std:fieldlookup-hstorefield.contained_by">
<span id="s-id2"></span><span id="std:fieldlookup-hstorefield.contained_by"></span><span id="id2"></span><h4><code class="docutils literal notranslate"><span class="pre">contained_by</span></code><a class="headerlink" href="#std:fieldlookup-hstorefield.contained_by" title="Permalink to this headline">¶</a></h4>
<p>This is the inverse of the <a class="reference internal" href="#std:fieldlookup-hstorefield.contains"><code class="xref std std-lookup docutils literal notranslate"><span class="pre">contains</span></code></a> lookup -
the objects returned will be those where the key-value pairs on the object are
a subset of those in the value passed. It uses the SQL operator <code class="docutils literal notranslate"><span class="pre">&lt;&#64;</span></code>. For
example:</p>
<div class="highlight-default notranslate"><div class="highlight"><pre><span></span><span class="gp">&gt;&gt;&gt; </span><span class="n">Dog</span><span class="o">.</span><span class="n">objects</span><span class="o">.</span><span class="n">create</span><span class="p">(</span><span class="n">name</span><span class="o">=</span><span class="s1">&#39;Rufus&#39;</span><span class="p">,</span> <span class="n">data</span><span class="o">=</span><span class="p">{</span><span class="s1">&#39;breed&#39;</span><span class="p">:</span> <span class="s1">&#39;labrador&#39;</span><span class="p">,</span> <span class="s1">&#39;owner&#39;</span><span class="p">:</span> <span class="s1">&#39;Bob&#39;</span><span class="p">})</span>
<span class="gp">&gt;&gt;&gt; </span><span class="n">Dog</span><span class="o">.</span><span class="n">objects</span><span class="o">.</span><span class="n">create</span><span class="p">(</span><span class="n">name</span><span class="o">=</span><span class="s1">&#39;Meg&#39;</span><span class="p">,</span> <span class="n">data</span><span class="o">=</span><span class="p">{</span><span class="s1">&#39;breed&#39;</span><span class="p">:</span> <span class="s1">&#39;collie&#39;</span><span class="p">,</span> <span class="s1">&#39;owner&#39;</span><span class="p">:</span> <span class="s1">&#39;Bob&#39;</span><span class="p">})</span>
<span class="gp">&gt;&gt;&gt; </span><span class="n">Dog</span><span class="o">.</span><span class="n">objects</span><span class="o">.</span><span class="n">create</span><span class="p">(</span><span class="n">name</span><span class="o">=</span><span class="s1">&#39;Fred&#39;</span><span class="p">,</span> <span class="n">data</span><span class="o">=</span><span class="p">{})</span>

<span class="gp">&gt;&gt;&gt; </span><span class="n">Dog</span><span class="o">.</span><span class="n">objects</span><span class="o">.</span><span class="n">filter</span><span class="p">(</span><span class="n">data__contained_by</span><span class="o">=</span><span class="p">{</span><span class="s1">&#39;breed&#39;</span><span class="p">:</span> <span class="s1">&#39;collie&#39;</span><span class="p">,</span> <span class="s1">&#39;owner&#39;</span><span class="p">:</span> <span class="s1">&#39;Bob&#39;</span><span class="p">})</span>
<span class="go">&lt;QuerySet [&lt;Dog: Meg&gt;, &lt;Dog: Fred&gt;]&gt;</span>

<span class="gp">&gt;&gt;&gt; </span><span class="n">Dog</span><span class="o">.</span><span class="n">objects</span><span class="o">.</span><span class="n">filter</span><span class="p">(</span><span class="n">data__contained_by</span><span class="o">=</span><span class="p">{</span><span class="s1">&#39;breed&#39;</span><span class="p">:</span> <span class="s1">&#39;collie&#39;</span><span class="p">})</span>
<span class="go">&lt;QuerySet [&lt;Dog: Fred&gt;]&gt;</span>
</pre></div>
</div>
</div>
<div class="section" id="s-has-key">
<span id="s-std:fieldlookup-hstorefield.has_key"></span><span id="has-key"></span><span id="std:fieldlookup-hstorefield.has_key"></span><h4><code class="docutils literal notranslate"><span class="pre">has_key</span></code><a class="headerlink" href="#has-key" title="Permalink to this headline">¶</a></h4>
<p>Returns objects where the given key is in the data. Uses the SQL operator
<code class="docutils literal notranslate"><span class="pre">?</span></code>. For example:</p>
<div class="highlight-default notranslate"><div class="highlight"><pre><span></span><span class="gp">&gt;&gt;&gt; </span><span class="n">Dog</span><span class="o">.</span><span class="n">objects</span><span class="o">.</span><span class="n">create</span><span class="p">(</span><span class="n">name</span><span class="o">=</span><span class="s1">&#39;Rufus&#39;</span><span class="p">,</span> <span class="n">data</span><span class="o">=</span><span class="p">{</span><span class="s1">&#39;breed&#39;</span><span class="p">:</span> <span class="s1">&#39;labrador&#39;</span><span class="p">})</span>
<span class="gp">&gt;&gt;&gt; </span><span class="n">Dog</span><span class="o">.</span><span class="n">objects</span><span class="o">.</span><span class="n">create</span><span class="p">(</span><span class="n">name</span><span class="o">=</span><span class="s1">&#39;Meg&#39;</span><span class="p">,</span> <span class="n">data</span><span class="o">=</span><span class="p">{</span><span class="s1">&#39;breed&#39;</span><span class="p">:</span> <span class="s1">&#39;collie&#39;</span><span class="p">,</span> <span class="s1">&#39;owner&#39;</span><span class="p">:</span> <span class="s1">&#39;Bob&#39;</span><span class="p">})</span>

<span class="gp">&gt;&gt;&gt; </span><span class="n">Dog</span><span class="o">.</span><span class="n">objects</span><span class="o">.</span><span class="n">filter</span><span class="p">(</span><span class="n">data__has_key</span><span class="o">=</span><span class="s1">&#39;owner&#39;</span><span class="p">)</span>
<span class="go">&lt;QuerySet [&lt;Dog: Meg&gt;]&gt;</span>
</pre></div>
</div>
</div>
<div class="section" id="s-has-any-keys">
<span id="s-std:fieldlookup-hstorefield.has_any_keys"></span><span id="has-any-keys"></span><span id="std:fieldlookup-hstorefield.has_any_keys"></span><h4><code class="docutils literal notranslate"><span class="pre">has_any_keys</span></code><a class="headerlink" href="#has-any-keys" title="Permalink to this headline">¶</a></h4>
<p>Returns objects where any of the given keys are in the data. Uses the SQL
operator <code class="docutils literal notranslate"><span class="pre">?|</span></code>. For example:</p>
<div class="highlight-default notranslate"><div class="highlight"><pre><span></span><span class="gp">&gt;&gt;&gt; </span><span class="n">Dog</span><span class="o">.</span><span class="n">objects</span><span class="o">.</span><span class="n">create</span><span class="p">(</span><span class="n">name</span><span class="o">=</span><span class="s1">&#39;Rufus&#39;</span><span class="p">,</span> <span class="n">data</span><span class="o">=</span><span class="p">{</span><span class="s1">&#39;breed&#39;</span><span class="p">:</span> <span class="s1">&#39;labrador&#39;</span><span class="p">})</span>
<span class="gp">&gt;&gt;&gt; </span><span class="n">Dog</span><span class="o">.</span><span class="n">objects</span><span class="o">.</span><span class="n">create</span><span class="p">(</span><span class="n">name</span><span class="o">=</span><span class="s1">&#39;Meg&#39;</span><span class="p">,</span> <span class="n">data</span><span class="o">=</span><span class="p">{</span><span class="s1">&#39;owner&#39;</span><span class="p">:</span> <span class="s1">&#39;Bob&#39;</span><span class="p">})</span>
<span class="gp">&gt;&gt;&gt; </span><span class="n">Dog</span><span class="o">.</span><span class="n">objects</span><span class="o">.</span><span class="n">create</span><span class="p">(</span><span class="n">name</span><span class="o">=</span><span class="s1">&#39;Fred&#39;</span><span class="p">,</span> <span class="n">data</span><span class="o">=</span><span class="p">{})</span>

<span class="gp">&gt;&gt;&gt; </span><span class="n">Dog</span><span class="o">.</span><span class="n">objects</span><span class="o">.</span><span class="n">filter</span><span class="p">(</span><span class="n">data__has_any_keys</span><span class="o">=</span><span class="p">[</span><span class="s1">&#39;owner&#39;</span><span class="p">,</span> <span class="s1">&#39;breed&#39;</span><span class="p">])</span>
<span class="go">&lt;QuerySet [&lt;Dog: Rufus&gt;, &lt;Dog: Meg&gt;]&gt;</span>
</pre></div>
</div>
</div>
<div class="section" id="s-has-keys">
<span id="s-std:fieldlookup-hstorefield.has_keys"></span><span id="has-keys"></span><span id="std:fieldlookup-hstorefield.has_keys"></span><h4><code class="docutils literal notranslate"><span class="pre">has_keys</span></code><a class="headerlink" href="#has-keys" title="Permalink to this headline">¶</a></h4>
<p>Returns objects where all of the given keys are in the data. Uses the SQL operator
<code class="docutils literal notranslate"><span class="pre">?&amp;</span></code>. For example:</p>
<div class="highlight-default notranslate"><div class="highlight"><pre><span></span><span class="gp">&gt;&gt;&gt; </span><span class="n">Dog</span><span class="o">.</span><span class="n">objects</span><span class="o">.</span><span class="n">create</span><span class="p">(</span><span class="n">name</span><span class="o">=</span><span class="s1">&#39;Rufus&#39;</span><span class="p">,</span> <span class="n">data</span><span class="o">=</span><span class="p">{})</span>
<span class="gp">&gt;&gt;&gt; </span><span class="n">Dog</span><span class="o">.</span><span class="n">objects</span><span class="o">.</span><span class="n">create</span><span class="p">(</span><span class="n">name</span><span class="o">=</span><span class="s1">&#39;Meg&#39;</span><span class="p">,</span> <span class="n">data</span><span class="o">=</span><span class="p">{</span><span class="s1">&#39;breed&#39;</span><span class="p">:</span> <span class="s1">&#39;collie&#39;</span><span class="p">,</span> <span class="s1">&#39;owner&#39;</span><span class="p">:</span> <span class="s1">&#39;Bob&#39;</span><span class="p">})</span>

<span class="gp">&gt;&gt;&gt; </span><span class="n">Dog</span><span class="o">.</span><span class="n">objects</span><span class="o">.</span><span class="n">filter</span><span class="p">(</span><span class="n">data__has_keys</span><span class="o">=</span><span class="p">[</span><span class="s1">&#39;breed&#39;</span><span class="p">,</span> <span class="s1">&#39;owner&#39;</span><span class="p">])</span>
<span class="go">&lt;QuerySet [&lt;Dog: Meg&gt;]&gt;</span>
</pre></div>
</div>
</div>
<div class="section" id="s-keys">
<span id="s-std:fieldlookup-hstorefield.keys"></span><span id="keys"></span><span id="std:fieldlookup-hstorefield.keys"></span><h4><code class="docutils literal notranslate"><span class="pre">keys</span></code><a class="headerlink" href="#keys" title="Permalink to this headline">¶</a></h4>
<p>Returns objects where the array of keys is the given value. Note that the order
is not guaranteed to be reliable, so this transform is mainly useful for using
in conjunction with lookups on
<a class="reference internal" href="#django.contrib.postgres.fields.ArrayField" title="django.contrib.postgres.fields.ArrayField"><code class="xref py py-class docutils literal notranslate"><span class="pre">ArrayField</span></code></a>. Uses the SQL function
<code class="docutils literal notranslate"><span class="pre">akeys()</span></code>. For example:</p>
<div class="highlight-default notranslate"><div class="highlight"><pre><span></span><span class="gp">&gt;&gt;&gt; </span><span class="n">Dog</span><span class="o">.</span><span class="n">objects</span><span class="o">.</span><span class="n">create</span><span class="p">(</span><span class="n">name</span><span class="o">=</span><span class="s1">&#39;Rufus&#39;</span><span class="p">,</span> <span class="n">data</span><span class="o">=</span><span class="p">{</span><span class="s1">&#39;toy&#39;</span><span class="p">:</span> <span class="s1">&#39;bone&#39;</span><span class="p">})</span>
<span class="gp">&gt;&gt;&gt; </span><span class="n">Dog</span><span class="o">.</span><span class="n">objects</span><span class="o">.</span><span class="n">create</span><span class="p">(</span><span class="n">name</span><span class="o">=</span><span class="s1">&#39;Meg&#39;</span><span class="p">,</span> <span class="n">data</span><span class="o">=</span><span class="p">{</span><span class="s1">&#39;breed&#39;</span><span class="p">:</span> <span class="s1">&#39;collie&#39;</span><span class="p">,</span> <span class="s1">&#39;owner&#39;</span><span class="p">:</span> <span class="s1">&#39;Bob&#39;</span><span class="p">})</span>

<span class="gp">&gt;&gt;&gt; </span><span class="n">Dog</span><span class="o">.</span><span class="n">objects</span><span class="o">.</span><span class="n">filter</span><span class="p">(</span><span class="n">data__keys__overlap</span><span class="o">=</span><span class="p">[</span><span class="s1">&#39;breed&#39;</span><span class="p">,</span> <span class="s1">&#39;toy&#39;</span><span class="p">])</span>
<span class="go">&lt;QuerySet [&lt;Dog: Rufus&gt;, &lt;Dog: Meg&gt;]&gt;</span>
</pre></div>
</div>
</div>
<div class="section" id="s-values">
<span id="s-std:fieldlookup-hstorefield.values"></span><span id="values"></span><span id="std:fieldlookup-hstorefield.values"></span><h4><code class="docutils literal notranslate"><span class="pre">values</span></code><a class="headerlink" href="#values" title="Permalink to this headline">¶</a></h4>
<p>Returns objects where the array of values is the given value. Note that the
order is not guaranteed to be reliable, so this transform is mainly useful for
using in conjunction with lookups on
<a class="reference internal" href="#django.contrib.postgres.fields.ArrayField" title="django.contrib.postgres.fields.ArrayField"><code class="xref py py-class docutils literal notranslate"><span class="pre">ArrayField</span></code></a>. Uses the SQL function
<code class="docutils literal notranslate"><span class="pre">avalues()</span></code>. For example:</p>
<div class="highlight-default notranslate"><div class="highlight"><pre><span></span><span class="gp">&gt;&gt;&gt; </span><span class="n">Dog</span><span class="o">.</span><span class="n">objects</span><span class="o">.</span><span class="n">create</span><span class="p">(</span><span class="n">name</span><span class="o">=</span><span class="s1">&#39;Rufus&#39;</span><span class="p">,</span> <span class="n">data</span><span class="o">=</span><span class="p">{</span><span class="s1">&#39;breed&#39;</span><span class="p">:</span> <span class="s1">&#39;labrador&#39;</span><span class="p">})</span>
<span class="gp">&gt;&gt;&gt; </span><span class="n">Dog</span><span class="o">.</span><span class="n">objects</span><span class="o">.</span><span class="n">create</span><span class="p">(</span><span class="n">name</span><span class="o">=</span><span class="s1">&#39;Meg&#39;</span><span class="p">,</span> <span class="n">data</span><span class="o">=</span><span class="p">{</span><span class="s1">&#39;breed&#39;</span><span class="p">:</span> <span class="s1">&#39;collie&#39;</span><span class="p">,</span> <span class="s1">&#39;owner&#39;</span><span class="p">:</span> <span class="s1">&#39;Bob&#39;</span><span class="p">})</span>

<span class="gp">&gt;&gt;&gt; </span><span class="n">Dog</span><span class="o">.</span><span class="n">objects</span><span class="o">.</span><span class="n">filter</span><span class="p">(</span><span class="n">data__values__contains</span><span class="o">=</span><span class="p">[</span><span class="s1">&#39;collie&#39;</span><span class="p">])</span>
<span class="go">&lt;QuerySet [&lt;Dog: Meg&gt;]&gt;</span>
</pre></div>
</div>
</div>
</div>
</div>
<div class="section" id="s-jsonfield">
<span id="jsonfield"></span><h2><code class="docutils literal notranslate"><span class="pre">JSONField</span></code><a class="headerlink" href="#jsonfield" title="Permalink to this headline">¶</a></h2>
<dl class="class">
<dt id="django.contrib.postgres.fields.JSONField">
<em class="property">class </em><code class="descname">JSONField</code>(<em>encoder=None</em>, <em>**options</em>)<a class="reference internal" href="../../../_modules/django/contrib/postgres/fields/jsonb.html#JSONField"><span class="viewcode-link">[source]</span></a><a class="headerlink" href="#django.contrib.postgres.fields.JSONField" title="Permalink to this definition">¶</a></dt>
<dd><p>A field for storing JSON encoded data. In Python the data is represented in
its Python native format: dictionaries, lists, strings, numbers, booleans
and <code class="docutils literal notranslate"><span class="pre">None</span></code>.</p>
<dl class="attribute">
<dt id="django.contrib.postgres.fields.JSONField.encoder">
<code class="descname">encoder</code><a class="headerlink" href="#django.contrib.postgres.fields.JSONField.encoder" title="Permalink to this definition">¶</a></dt>
<dd><div class="versionadded">
<span class="title">New in Django 1.11.</span> </div>
<p>An optional JSON-encoding class to serialize data types not supported
by the standard JSON serializer (<code class="docutils literal notranslate"><span class="pre">datetime</span></code>, <code class="docutils literal notranslate"><span class="pre">uuid</span></code>, etc.). For
example, you can use the
<a class="reference internal" href="../../../topics/serialization.html#django.core.serializers.json.DjangoJSONEncoder" title="django.core.serializers.json.DjangoJSONEncoder"><code class="xref py py-class docutils literal notranslate"><span class="pre">DjangoJSONEncoder</span></code></a> class or any
other <a class="reference external" href="https://docs.python.org/3/library/json.html#json.JSONEncoder" title="(in Python v3.7)"><code class="xref py py-class docutils literal notranslate"><span class="pre">json.JSONEncoder</span></code></a> subclass.</p>
<p>When the value is retrieved from the database, it will be in the format
chosen by the custom encoder (most often a string), so you’ll need to
take extra steps to convert the value back to the initial data type
(<a class="reference internal" href="../../models/instances.html#django.db.models.Model.from_db" title="django.db.models.Model.from_db"><code class="xref py py-meth docutils literal notranslate"><span class="pre">Model.from_db()</span></code></a> and
<a class="reference internal" href="../../models/fields.html#django.db.models.Field.from_db_value" title="django.db.models.Field.from_db_value"><code class="xref py py-meth docutils literal notranslate"><span class="pre">Field.from_db_value()</span></code></a>
are two possible hooks for that purpose). Your deserialization may need
to account for the fact that you can’t be certain of the input type.
For example, you run the risk of returning a <code class="docutils literal notranslate"><span class="pre">datetime</span></code> that was
actually a string that just happened to be in the same format chosen
for <code class="docutils literal notranslate"><span class="pre">datetime</span></code>s.</p>
</dd></dl>

<p>If you give the field a <a class="reference internal" href="../../models/fields.html#django.db.models.Field.default" title="django.db.models.Field.default"><code class="xref py py-attr docutils literal notranslate"><span class="pre">default</span></code></a>, ensure
it’s a callable such as <code class="docutils literal notranslate"><span class="pre">dict</span></code> (for an empty default) or a callable that
returns a dict (such as a function). Incorrectly using <code class="docutils literal notranslate"><span class="pre">default={}</span></code>
creates a mutable default that is shared between all instances of
<code class="docutils literal notranslate"><span class="pre">JSONField</span></code>.</p>
</dd></dl>

<div class="admonition note">
<p class="first admonition-title">Note</p>
<p>PostgreSQL has two native JSON based data types: <code class="docutils literal notranslate"><span class="pre">json</span></code> and <code class="docutils literal notranslate"><span class="pre">jsonb</span></code>.
The main difference between them is how they are stored and how they can be
queried. PostgreSQL’s <code class="docutils literal notranslate"><span class="pre">json</span></code> field is stored as the original string
representation of the JSON and must be decoded on the fly when queried
based on keys. The <code class="docutils literal notranslate"><span class="pre">jsonb</span></code> field is stored based on the actual structure
of the JSON which allows indexing. The trade-off is a small additional cost
on writing to the <code class="docutils literal notranslate"><span class="pre">jsonb</span></code> field. <code class="docutils literal notranslate"><span class="pre">JSONField</span></code> uses <code class="docutils literal notranslate"><span class="pre">jsonb</span></code>.</p>
<p class="last"><strong>As a result, this field requires PostgreSQL ≥ 9.4</strong>.</p>
</div>
<div class="section" id="s-querying-jsonfield">
<span id="querying-jsonfield"></span><h3>Querying <code class="docutils literal notranslate"><span class="pre">JSONField</span></code><a class="headerlink" href="#querying-jsonfield" title="Permalink to this headline">¶</a></h3>
<p>We will use the following example model:</p>
<div class="highlight-default notranslate"><div class="highlight"><pre><span></span><span class="kn">from</span> <span class="nn">django.contrib.postgres.fields</span> <span class="k">import</span> <span class="n">JSONField</span>
<span class="kn">from</span> <span class="nn">django.db</span> <span class="k">import</span> <span class="n">models</span>

<span class="k">class</span> <span class="nc">Dog</span><span class="p">(</span><span class="n">models</span><span class="o">.</span><span class="n">Model</span><span class="p">):</span>
    <span class="n">name</span> <span class="o">=</span> <span class="n">models</span><span class="o">.</span><span class="n">CharField</span><span class="p">(</span><span class="n">max_length</span><span class="o">=</span><span class="mi">200</span><span class="p">)</span>
    <span class="n">data</span> <span class="o">=</span> <span class="n">JSONField</span><span class="p">()</span>

    <span class="k">def</span> <span class="nf">__str__</span><span class="p">(</span><span class="bp">self</span><span class="p">):</span>  <span class="c1"># __unicode__ on Python 2</span>
        <span class="k">return</span> <span class="bp">self</span><span class="o">.</span><span class="n">name</span>
</pre></div>
</div>
<div class="section" id="s-key-index-and-path-lookups">
<span id="s-std:fieldlookup-jsonfield.key"></span><span id="key-index-and-path-lookups"></span><span id="std:fieldlookup-jsonfield.key"></span><h4>Key, index, and path lookups<a class="headerlink" href="#key-index-and-path-lookups" title="Permalink to this headline">¶</a></h4>
<p>To query based on a given dictionary key, simply use that key as the lookup
name:</p>
<div class="highlight-default notranslate"><div class="highlight"><pre><span></span><span class="gp">&gt;&gt;&gt; </span><span class="n">Dog</span><span class="o">.</span><span class="n">objects</span><span class="o">.</span><span class="n">create</span><span class="p">(</span><span class="n">name</span><span class="o">=</span><span class="s1">&#39;Rufus&#39;</span><span class="p">,</span> <span class="n">data</span><span class="o">=</span><span class="p">{</span>
<span class="gp">... </span>    <span class="s1">&#39;breed&#39;</span><span class="p">:</span> <span class="s1">&#39;labrador&#39;</span><span class="p">,</span>
<span class="gp">... </span>    <span class="s1">&#39;owner&#39;</span><span class="p">:</span> <span class="p">{</span>
<span class="gp">... </span>        <span class="s1">&#39;name&#39;</span><span class="p">:</span> <span class="s1">&#39;Bob&#39;</span><span class="p">,</span>
<span class="gp">... </span>        <span class="s1">&#39;other_pets&#39;</span><span class="p">:</span> <span class="p">[{</span>
<span class="gp">... </span>            <span class="s1">&#39;name&#39;</span><span class="p">:</span> <span class="s1">&#39;Fishy&#39;</span><span class="p">,</span>
<span class="gp">... </span>        <span class="p">}],</span>
<span class="gp">... </span>    <span class="p">},</span>
<span class="gp">... </span><span class="p">})</span>
<span class="gp">&gt;&gt;&gt; </span><span class="n">Dog</span><span class="o">.</span><span class="n">objects</span><span class="o">.</span><span class="n">create</span><span class="p">(</span><span class="n">name</span><span class="o">=</span><span class="s1">&#39;Meg&#39;</span><span class="p">,</span> <span class="n">data</span><span class="o">=</span><span class="p">{</span><span class="s1">&#39;breed&#39;</span><span class="p">:</span> <span class="s1">&#39;collie&#39;</span><span class="p">})</span>

<span class="gp">&gt;&gt;&gt; </span><span class="n">Dog</span><span class="o">.</span><span class="n">objects</span><span class="o">.</span><span class="n">filter</span><span class="p">(</span><span class="n">data__breed</span><span class="o">=</span><span class="s1">&#39;collie&#39;</span><span class="p">)</span>
<span class="go">&lt;QuerySet [&lt;Dog: Meg&gt;]&gt;</span>
</pre></div>
</div>
<p>Multiple keys can be chained together to form a path lookup:</p>
<div class="highlight-default notranslate"><div class="highlight"><pre><span></span><span class="gp">&gt;&gt;&gt; </span><span class="n">Dog</span><span class="o">.</span><span class="n">objects</span><span class="o">.</span><span class="n">filter</span><span class="p">(</span><span class="n">data__owner__name</span><span class="o">=</span><span class="s1">&#39;Bob&#39;</span><span class="p">)</span>
<span class="go">&lt;QuerySet [&lt;Dog: Rufus&gt;]&gt;</span>
</pre></div>
</div>
<p>If the key is an integer, it will be interpreted as an index lookup in an
array:</p>
<div class="highlight-default notranslate"><div class="highlight"><pre><span></span><span class="gp">&gt;&gt;&gt; </span><span class="n">Dog</span><span class="o">.</span><span class="n">objects</span><span class="o">.</span><span class="n">filter</span><span class="p">(</span><span class="n">data__owner__other_pets__0__name</span><span class="o">=</span><span class="s1">&#39;Fishy&#39;</span><span class="p">)</span>
<span class="go">&lt;QuerySet [&lt;Dog: Rufus&gt;]&gt;</span>
</pre></div>
</div>
<p>If the key you wish to query by clashes with the name of another lookup, use
the <a class="reference internal" href="#std:fieldlookup-jsonfield.contains"><code class="xref std std-lookup docutils literal notranslate"><span class="pre">jsonfield.contains</span></code></a> lookup instead.</p>
<p>If only one key or index is used, the SQL operator <code class="docutils literal notranslate"><span class="pre">-&gt;</span></code> is used. If multiple
operators are used then the <code class="docutils literal notranslate"><span class="pre">#&gt;</span></code> operator is used.</p>
<div class="admonition warning">
<p class="first admonition-title">Warning</p>
<p class="last">Since any string could be a key in a JSON object, any lookup other than
those listed below will be interpreted as a key lookup. No errors are
raised. Be extra careful for typing mistakes, and always check your queries
work as you intend.</p>
</div>
</div>
<div class="section" id="s-containment-and-key-operations">
<span id="containment-and-key-operations"></span><h4>Containment and key operations<a class="headerlink" href="#containment-and-key-operations" title="Permalink to this headline">¶</a></h4>
<span class="target" id="std:fieldlookup-jsonfield.contains"></span><span class="target" id="std:fieldlookup-jsonfield.contained_by"></span><span class="target" id="std:fieldlookup-jsonfield.has_key"></span><span class="target" id="std:fieldlookup-jsonfield.has_any_keys"></span><p id="std:fieldlookup-jsonfield.has_keys"><a class="reference internal" href="#django.contrib.postgres.fields.JSONField" title="django.contrib.postgres.fields.JSONField"><code class="xref py py-class docutils literal notranslate"><span class="pre">JSONField</span></code></a> shares lookups relating to
containment and keys with <a class="reference internal" href="#django.contrib.postgres.fields.HStoreField" title="django.contrib.postgres.fields.HStoreField"><code class="xref py py-class docutils literal notranslate"><span class="pre">HStoreField</span></code></a>.</p>
<ul class="simple">
<li><a class="reference internal" href="#std:fieldlookup-hstorefield.contains"><code class="xref std std-lookup docutils literal notranslate"><span class="pre">contains</span></code></a> (accepts any JSON rather than
just a dictionary of strings)</li>
<li><a class="reference internal" href="#std:fieldlookup-hstorefield.contained_by"><code class="xref std std-lookup docutils literal notranslate"><span class="pre">contained_by</span></code></a> (accepts any JSON
rather than just a dictionary of strings)</li>
<li><a class="reference internal" href="#std:fieldlookup-hstorefield.has_key"><code class="xref std std-lookup docutils literal notranslate"><span class="pre">has_key</span></code></a></li>
<li><a class="reference internal" href="#std:fieldlookup-hstorefield.has_any_keys"><code class="xref std std-lookup docutils literal notranslate"><span class="pre">has_any_keys</span></code></a></li>
<li><a class="reference internal" href="#std:fieldlookup-hstorefield.has_keys"><code class="xref std std-lookup docutils literal notranslate"><span class="pre">has_keys</span></code></a></li>
</ul>
</div>
</div>
</div>
<div class="section" id="s-range-fields">
<span id="s-id3"></span><span id="range-fields"></span><span id="id3"></span><h2>Range Fields<a class="headerlink" href="#range-fields" title="Permalink to this headline">¶</a></h2>
<p>There are five range field types, corresponding to the built-in range types in
PostgreSQL. These fields are used to store a range of values; for example the
start and end timestamps of an event, or the range of ages an activity is
suitable for.</p>
<p>All of the range fields translate to <a class="reference external" href="http://initd.org/psycopg/docs/extras.html#adapt-range" title="(in Psycopg v2.8)"><span class="xref std std-ref">psycopg2 Range objects</span></a> in python, but also accept tuples as input if no bounds
information is necessary. The default is lower bound included, upper bound
excluded; that is, <code class="docutils literal notranslate"><span class="pre">[)</span></code>.</p>
<div class="section" id="s-integerrangefield">
<span id="integerrangefield"></span><h3><code class="docutils literal notranslate"><span class="pre">IntegerRangeField</span></code><a class="headerlink" href="#integerrangefield" title="Permalink to this headline">¶</a></h3>
<dl class="class">
<dt id="django.contrib.postgres.fields.IntegerRangeField">
<em class="property">class </em><code class="descname">IntegerRangeField</code>(<em>**options</em>)<a class="reference internal" href="../../../_modules/django/contrib/postgres/fields/ranges.html#IntegerRangeField"><span class="viewcode-link">[source]</span></a><a class="headerlink" href="#django.contrib.postgres.fields.IntegerRangeField" title="Permalink to this definition">¶</a></dt>
<dd><p>Stores a range of integers. Based on an
<a class="reference internal" href="../../models/fields.html#django.db.models.IntegerField" title="django.db.models.IntegerField"><code class="xref py py-class docutils literal notranslate"><span class="pre">IntegerField</span></code></a>. Represented by an <code class="docutils literal notranslate"><span class="pre">int4range</span></code> in
the database and a <a class="reference external" href="http://initd.org/psycopg/docs/extras.html#psycopg2.extras.NumericRange" title="(in Psycopg v2.8)"><code class="xref py py-class docutils literal notranslate"><span class="pre">NumericRange</span></code></a> in
Python.</p>
<p>Regardless of the bounds specified when saving the data, PostgreSQL always
returns a range in a canonical form that includes the lower bound and
excludes the upper bound; that is <code class="docutils literal notranslate"><span class="pre">[)</span></code>.</p>
</dd></dl>

</div>
<div class="section" id="s-bigintegerrangefield">
<span id="bigintegerrangefield"></span><h3><code class="docutils literal notranslate"><span class="pre">BigIntegerRangeField</span></code><a class="headerlink" href="#bigintegerrangefield" title="Permalink to this headline">¶</a></h3>
<dl class="class">
<dt id="django.contrib.postgres.fields.BigIntegerRangeField">
<em class="property">class </em><code class="descname">BigIntegerRangeField</code>(<em>**options</em>)<a class="reference internal" href="../../../_modules/django/contrib/postgres/fields/ranges.html#BigIntegerRangeField"><span class="viewcode-link">[source]</span></a><a class="headerlink" href="#django.contrib.postgres.fields.BigIntegerRangeField" title="Permalink to this definition">¶</a></dt>
<dd><p>Stores a range of large integers. Based on a
<a class="reference internal" href="../../models/fields.html#django.db.models.BigIntegerField" title="django.db.models.BigIntegerField"><code class="xref py py-class docutils literal notranslate"><span class="pre">BigIntegerField</span></code></a>. Represented by an <code class="docutils literal notranslate"><span class="pre">int8range</span></code>
in the database and a <a class="reference external" href="http://initd.org/psycopg/docs/extras.html#psycopg2.extras.NumericRange" title="(in Psycopg v2.8)"><code class="xref py py-class docutils literal notranslate"><span class="pre">NumericRange</span></code></a> in
Python.</p>
<p>Regardless of the bounds specified when saving the data, PostgreSQL always
returns a range in a canonical form that includes the lower bound and
excludes the upper bound; that is <code class="docutils literal notranslate"><span class="pre">[)</span></code>.</p>
</dd></dl>

</div>
<div class="section" id="s-floatrangefield">
<span id="floatrangefield"></span><h3><code class="docutils literal notranslate"><span class="pre">FloatRangeField</span></code><a class="headerlink" href="#floatrangefield" title="Permalink to this headline">¶</a></h3>
<dl class="class">
<dt id="django.contrib.postgres.fields.FloatRangeField">
<em class="property">class </em><code class="descname">FloatRangeField</code>(<em>**options</em>)<a class="reference internal" href="../../../_modules/django/contrib/postgres/fields/ranges.html#FloatRangeField"><span class="viewcode-link">[source]</span></a><a class="headerlink" href="#django.contrib.postgres.fields.FloatRangeField" title="Permalink to this definition">¶</a></dt>
<dd><p>Stores a range of floating point values. Based on a
<a class="reference internal" href="../../models/fields.html#django.db.models.FloatField" title="django.db.models.FloatField"><code class="xref py py-class docutils literal notranslate"><span class="pre">FloatField</span></code></a>. Represented by a <code class="docutils literal notranslate"><span class="pre">numrange</span></code> in the
database and a <a class="reference external" href="http://initd.org/psycopg/docs/extras.html#psycopg2.extras.NumericRange" title="(in Psycopg v2.8)"><code class="xref py py-class docutils literal notranslate"><span class="pre">NumericRange</span></code></a> in Python.</p>
</dd></dl>

</div>
<div class="section" id="s-datetimerangefield">
<span id="datetimerangefield"></span><h3><code class="docutils literal notranslate"><span class="pre">DateTimeRangeField</span></code><a class="headerlink" href="#datetimerangefield" title="Permalink to this headline">¶</a></h3>
<dl class="class">
<dt id="django.contrib.postgres.fields.DateTimeRangeField">
<em class="property">class </em><code class="descname">DateTimeRangeField</code>(<em>**options</em>)<a class="reference internal" href="../../../_modules/django/contrib/postgres/fields/ranges.html#DateTimeRangeField"><span class="viewcode-link">[source]</span></a><a class="headerlink" href="#django.contrib.postgres.fields.DateTimeRangeField" title="Permalink to this definition">¶</a></dt>
<dd><p>Stores a range of timestamps. Based on a
<a class="reference internal" href="../../models/fields.html#django.db.models.DateTimeField" title="django.db.models.DateTimeField"><code class="xref py py-class docutils literal notranslate"><span class="pre">DateTimeField</span></code></a>. Represented by a <code class="docutils literal notranslate"><span class="pre">tstzrange</span></code> in
the database and a <a class="reference external" href="http://initd.org/psycopg/docs/extras.html#psycopg2.extras.DateTimeTZRange" title="(in Psycopg v2.8)"><code class="xref py py-class docutils literal notranslate"><span class="pre">DateTimeTZRange</span></code></a> in
Python.</p>
</dd></dl>

</div>
<div class="section" id="s-daterangefield">
<span id="daterangefield"></span><h3><code class="docutils literal notranslate"><span class="pre">DateRangeField</span></code><a class="headerlink" href="#daterangefield" title="Permalink to this headline">¶</a></h3>
<dl class="class">
<dt id="django.contrib.postgres.fields.DateRangeField">
<em class="property">class </em><code class="descname">DateRangeField</code>(<em>**options</em>)<a class="reference internal" href="../../../_modules/django/contrib/postgres/fields/ranges.html#DateRangeField"><span class="viewcode-link">[source]</span></a><a class="headerlink" href="#django.contrib.postgres.fields.DateRangeField" title="Permalink to this definition">¶</a></dt>
<dd><p>Stores a range of dates. Based on a
<a class="reference internal" href="../../models/fields.html#django.db.models.DateField" title="django.db.models.DateField"><code class="xref py py-class docutils literal notranslate"><span class="pre">DateField</span></code></a>. Represented by a <code class="docutils literal notranslate"><span class="pre">daterange</span></code> in the
database and a <a class="reference external" href="http://initd.org/psycopg/docs/extras.html#psycopg2.extras.DateRange" title="(in Psycopg v2.8)"><code class="xref py py-class docutils literal notranslate"><span class="pre">DateRange</span></code></a> in Python.</p>
<p>Regardless of the bounds specified when saving the data, PostgreSQL always
returns a range in a canonical form that includes the lower bound and
excludes the upper bound; that is <code class="docutils literal notranslate"><span class="pre">[)</span></code>.</p>
</dd></dl>

</div>
<div class="section" id="s-querying-range-fields">
<span id="querying-range-fields"></span><h3>Querying Range Fields<a class="headerlink" href="#querying-range-fields" title="Permalink to this headline">¶</a></h3>
<p>There are a number of custom lookups and transforms for range fields. They are
available on all the above fields, but we will use the following example
model:</p>
<div class="highlight-default notranslate"><div class="highlight"><pre><span></span><span class="kn">from</span> <span class="nn">django.contrib.postgres.fields</span> <span class="k">import</span> <span class="n">IntegerRangeField</span>
<span class="kn">from</span> <span class="nn">django.db</span> <span class="k">import</span> <span class="n">models</span>

<span class="k">class</span> <span class="nc">Event</span><span class="p">(</span><span class="n">models</span><span class="o">.</span><span class="n">Model</span><span class="p">):</span>
    <span class="n">name</span> <span class="o">=</span> <span class="n">models</span><span class="o">.</span><span class="n">CharField</span><span class="p">(</span><span class="n">max_length</span><span class="o">=</span><span class="mi">200</span><span class="p">)</span>
    <span class="n">ages</span> <span class="o">=</span> <span class="n">IntegerRangeField</span><span class="p">()</span>
    <span class="n">start</span> <span class="o">=</span> <span class="n">models</span><span class="o">.</span><span class="n">DateTimeField</span><span class="p">()</span>

    <span class="k">def</span> <span class="nf">__str__</span><span class="p">(</span><span class="bp">self</span><span class="p">):</span>  <span class="c1"># __unicode__ on Python 2</span>
        <span class="k">return</span> <span class="bp">self</span><span class="o">.</span><span class="n">name</span>
</pre></div>
</div>
<p>We will also use the following example objects:</p>
<div class="highlight-default notranslate"><div class="highlight"><pre><span></span><span class="gp">&gt;&gt;&gt; </span><span class="kn">import</span> <span class="nn">datetime</span>
<span class="gp">&gt;&gt;&gt; </span><span class="kn">from</span> <span class="nn">django.utils</span> <span class="k">import</span> <span class="n">timezone</span>
<span class="gp">&gt;&gt;&gt; </span><span class="n">now</span> <span class="o">=</span> <span class="n">timezone</span><span class="o">.</span><span class="n">now</span><span class="p">()</span>
<span class="gp">&gt;&gt;&gt; </span><span class="n">Event</span><span class="o">.</span><span class="n">objects</span><span class="o">.</span><span class="n">create</span><span class="p">(</span><span class="n">name</span><span class="o">=</span><span class="s1">&#39;Soft play&#39;</span><span class="p">,</span> <span class="n">ages</span><span class="o">=</span><span class="p">(</span><span class="mi">0</span><span class="p">,</span> <span class="mi">10</span><span class="p">),</span> <span class="n">start</span><span class="o">=</span><span class="n">now</span><span class="p">)</span>
<span class="gp">&gt;&gt;&gt; </span><span class="n">Event</span><span class="o">.</span><span class="n">objects</span><span class="o">.</span><span class="n">create</span><span class="p">(</span><span class="n">name</span><span class="o">=</span><span class="s1">&#39;Pub trip&#39;</span><span class="p">,</span> <span class="n">ages</span><span class="o">=</span><span class="p">(</span><span class="mi">21</span><span class="p">,</span> <span class="kc">None</span><span class="p">),</span> <span class="n">start</span><span class="o">=</span><span class="n">now</span> <span class="o">-</span> <span class="n">datetime</span><span class="o">.</span><span class="n">timedelta</span><span class="p">(</span><span class="n">days</span><span class="o">=</span><span class="mi">1</span><span class="p">))</span>
</pre></div>
</div>
<p>and <code class="docutils literal notranslate"><span class="pre">NumericRange</span></code>:</p>
<div class="highlight-default notranslate"><div class="highlight"><pre><span></span><span class="gp">&gt;&gt;&gt; </span><span class="kn">from</span> <span class="nn">psycopg2.extras</span> <span class="k">import</span> <span class="n">NumericRange</span>
</pre></div>
</div>
<div class="section" id="s-containment-functions">
<span id="containment-functions"></span><h4>Containment functions<a class="headerlink" href="#containment-functions" title="Permalink to this headline">¶</a></h4>
<p>As with other PostgreSQL fields, there are three standard containment
operators: <code class="docutils literal notranslate"><span class="pre">contains</span></code>, <code class="docutils literal notranslate"><span class="pre">contained_by</span></code> and <code class="docutils literal notranslate"><span class="pre">overlap</span></code>, using the SQL
operators <code class="docutils literal notranslate"><span class="pre">&#64;&gt;</span></code>, <code class="docutils literal notranslate"><span class="pre">&lt;&#64;</span></code>, and <code class="docutils literal notranslate"><span class="pre">&amp;&amp;</span></code> respectively.</p>
<div class="section" id="s-std:fieldlookup-rangefield.contains">
<span id="s-id4"></span><span id="std:fieldlookup-rangefield.contains"></span><span id="id4"></span><h5><code class="docutils literal notranslate"><span class="pre">contains</span></code><a class="headerlink" href="#std:fieldlookup-rangefield.contains" title="Permalink to this headline">¶</a></h5>
<div class="highlight-default notranslate"><div class="highlight"><pre><span></span><span class="gp">&gt;&gt;&gt; </span><span class="n">Event</span><span class="o">.</span><span class="n">objects</span><span class="o">.</span><span class="n">filter</span><span class="p">(</span><span class="n">ages__contains</span><span class="o">=</span><span class="n">NumericRange</span><span class="p">(</span><span class="mi">4</span><span class="p">,</span> <span class="mi">5</span><span class="p">))</span>
<span class="go">&lt;QuerySet [&lt;Event: Soft play&gt;]&gt;</span>
</pre></div>
</div>
</div>
<div class="section" id="s-std:fieldlookup-rangefield.contained_by">
<span id="s-id5"></span><span id="std:fieldlookup-rangefield.contained_by"></span><span id="id5"></span><h5><code class="docutils literal notranslate"><span class="pre">contained_by</span></code><a class="headerlink" href="#std:fieldlookup-rangefield.contained_by" title="Permalink to this headline">¶</a></h5>
<div class="highlight-default notranslate"><div class="highlight"><pre><span></span><span class="gp">&gt;&gt;&gt; </span><span class="n">Event</span><span class="o">.</span><span class="n">objects</span><span class="o">.</span><span class="n">filter</span><span class="p">(</span><span class="n">ages__contained_by</span><span class="o">=</span><span class="n">NumericRange</span><span class="p">(</span><span class="mi">0</span><span class="p">,</span> <span class="mi">15</span><span class="p">))</span>
<span class="go">&lt;QuerySet [&lt;Event: Soft play&gt;]&gt;</span>
</pre></div>
</div>
<p>The <code class="docutils literal notranslate"><span class="pre">contained_by</span></code> lookup is also available on the non-range field types:
<a class="reference internal" href="../../models/fields.html#django.db.models.IntegerField" title="django.db.models.IntegerField"><code class="xref py py-class docutils literal notranslate"><span class="pre">IntegerField</span></code></a>,
<a class="reference internal" href="../../models/fields.html#django.db.models.BigIntegerField" title="django.db.models.BigIntegerField"><code class="xref py py-class docutils literal notranslate"><span class="pre">BigIntegerField</span></code></a>,
<a class="reference internal" href="../../models/fields.html#django.db.models.FloatField" title="django.db.models.FloatField"><code class="xref py py-class docutils literal notranslate"><span class="pre">FloatField</span></code></a>, <a class="reference internal" href="../../models/fields.html#django.db.models.DateField" title="django.db.models.DateField"><code class="xref py py-class docutils literal notranslate"><span class="pre">DateField</span></code></a>,
and <a class="reference internal" href="../../models/fields.html#django.db.models.DateTimeField" title="django.db.models.DateTimeField"><code class="xref py py-class docutils literal notranslate"><span class="pre">DateTimeField</span></code></a>. For example:</p>
<div class="highlight-default notranslate"><div class="highlight"><pre><span></span><span class="gp">&gt;&gt;&gt; </span><span class="kn">from</span> <span class="nn">psycopg2.extras</span> <span class="k">import</span> <span class="n">DateTimeTZRange</span>
<span class="gp">&gt;&gt;&gt; </span><span class="n">Event</span><span class="o">.</span><span class="n">objects</span><span class="o">.</span><span class="n">filter</span><span class="p">(</span><span class="n">start__contained_by</span><span class="o">=</span><span class="n">DateTimeTZRange</span><span class="p">(</span>
<span class="gp">... </span>    <span class="n">timezone</span><span class="o">.</span><span class="n">now</span><span class="p">()</span> <span class="o">-</span> <span class="n">datetime</span><span class="o">.</span><span class="n">timedelta</span><span class="p">(</span><span class="n">hours</span><span class="o">=</span><span class="mi">1</span><span class="p">),</span>
<span class="gp">... </span>    <span class="n">timezone</span><span class="o">.</span><span class="n">now</span><span class="p">()</span> <span class="o">+</span> <span class="n">datetime</span><span class="o">.</span><span class="n">timedelta</span><span class="p">(</span><span class="n">hours</span><span class="o">=</span><span class="mi">1</span><span class="p">),</span>
<span class="gp">... </span><span class="p">)</span>
<span class="go">&lt;QuerySet [&lt;Event: Soft play&gt;]&gt;</span>
</pre></div>
</div>
</div>
<div class="section" id="s-std:fieldlookup-rangefield.overlap">
<span id="s-id6"></span><span id="std:fieldlookup-rangefield.overlap"></span><span id="id6"></span><h5><code class="docutils literal notranslate"><span class="pre">overlap</span></code><a class="headerlink" href="#std:fieldlookup-rangefield.overlap" title="Permalink to this headline">¶</a></h5>
<div class="highlight-default notranslate"><div class="highlight"><pre><span></span><span class="gp">&gt;&gt;&gt; </span><span class="n">Event</span><span class="o">.</span><span class="n">objects</span><span class="o">.</span><span class="n">filter</span><span class="p">(</span><span class="n">ages__overlap</span><span class="o">=</span><span class="n">NumericRange</span><span class="p">(</span><span class="mi">8</span><span class="p">,</span> <span class="mi">12</span><span class="p">))</span>
<span class="go">&lt;QuerySet [&lt;Event: Soft play&gt;]&gt;</span>
</pre></div>
</div>
</div>
</div>
<div class="section" id="s-comparison-functions">
<span id="comparison-functions"></span><h4>Comparison functions<a class="headerlink" href="#comparison-functions" title="Permalink to this headline">¶</a></h4>
<p>Range fields support the standard lookups: <a class="reference internal" href="../../models/querysets.html#std:fieldlookup-lt"><code class="xref std std-lookup docutils literal notranslate"><span class="pre">lt</span></code></a>, <a class="reference internal" href="../../models/querysets.html#std:fieldlookup-gt"><code class="xref std std-lookup docutils literal notranslate"><span class="pre">gt</span></code></a>,
<a class="reference internal" href="../../models/querysets.html#std:fieldlookup-lte"><code class="xref std std-lookup docutils literal notranslate"><span class="pre">lte</span></code></a> and <a class="reference internal" href="../../models/querysets.html#std:fieldlookup-gte"><code class="xref std std-lookup docutils literal notranslate"><span class="pre">gte</span></code></a>. These are not particularly helpful - they
compare the lower bounds first and then the upper bounds only if necessary.
This is also the strategy used to order by a range field. It is better to use
the specific range comparison operators.</p>
<div class="section" id="s-fully-lt">
<span id="s-std:fieldlookup-rangefield.fully_lt"></span><span id="fully-lt"></span><span id="std:fieldlookup-rangefield.fully_lt"></span><h5><code class="docutils literal notranslate"><span class="pre">fully_lt</span></code><a class="headerlink" href="#fully-lt" title="Permalink to this headline">¶</a></h5>
<p>The returned ranges are strictly less than the passed range. In other words,
all the points in the returned range are less than all those in the passed
range.</p>
<div class="highlight-default notranslate"><div class="highlight"><pre><span></span><span class="gp">&gt;&gt;&gt; </span><span class="n">Event</span><span class="o">.</span><span class="n">objects</span><span class="o">.</span><span class="n">filter</span><span class="p">(</span><span class="n">ages__fully_lt</span><span class="o">=</span><span class="n">NumericRange</span><span class="p">(</span><span class="mi">11</span><span class="p">,</span> <span class="mi">15</span><span class="p">))</span>
<span class="go">&lt;QuerySet [&lt;Event: Soft play&gt;]&gt;</span>
</pre></div>
</div>
</div>
<div class="section" id="s-fully-gt">
<span id="s-std:fieldlookup-rangefield.fully_gt"></span><span id="fully-gt"></span><span id="std:fieldlookup-rangefield.fully_gt"></span><h5><code class="docutils literal notranslate"><span class="pre">fully_gt</span></code><a class="headerlink" href="#fully-gt" title="Permalink to this headline">¶</a></h5>
<p>The returned ranges are strictly greater than the passed range. In other words,
the all the points in the returned range are greater than all those in the
passed range.</p>
<div class="highlight-default notranslate"><div class="highlight"><pre><span></span><span class="gp">&gt;&gt;&gt; </span><span class="n">Event</span><span class="o">.</span><span class="n">objects</span><span class="o">.</span><span class="n">filter</span><span class="p">(</span><span class="n">ages__fully_gt</span><span class="o">=</span><span class="n">NumericRange</span><span class="p">(</span><span class="mi">11</span><span class="p">,</span> <span class="mi">15</span><span class="p">))</span>
<span class="go">&lt;QuerySet [&lt;Event: Pub trip&gt;]&gt;</span>
</pre></div>
</div>
</div>
<div class="section" id="s-not-lt">
<span id="s-std:fieldlookup-rangefield.not_lt"></span><span id="not-lt"></span><span id="std:fieldlookup-rangefield.not_lt"></span><h5><code class="docutils literal notranslate"><span class="pre">not_lt</span></code><a class="headerlink" href="#not-lt" title="Permalink to this headline">¶</a></h5>
<p>The returned ranges do not contain any points less than the passed range, that
is the lower bound of the returned range is at least the lower bound of the
passed range.</p>
<div class="highlight-default notranslate"><div class="highlight"><pre><span></span><span class="gp">&gt;&gt;&gt; </span><span class="n">Event</span><span class="o">.</span><span class="n">objects</span><span class="o">.</span><span class="n">filter</span><span class="p">(</span><span class="n">ages__not_lt</span><span class="o">=</span><span class="n">NumericRange</span><span class="p">(</span><span class="mi">0</span><span class="p">,</span> <span class="mi">15</span><span class="p">))</span>
<span class="go">&lt;QuerySet [&lt;Event: Soft play&gt;, &lt;Event: Pub trip&gt;]&gt;</span>
</pre></div>
</div>
</div>
<div class="section" id="s-not-gt">
<span id="s-std:fieldlookup-rangefield.not_gt"></span><span id="not-gt"></span><span id="std:fieldlookup-rangefield.not_gt"></span><h5><code class="docutils literal notranslate"><span class="pre">not_gt</span></code><a class="headerlink" href="#not-gt" title="Permalink to this headline">¶</a></h5>
<p>The returned ranges do not contain any points greater than the passed range, that
is the upper bound of the returned range is at most the upper bound of the
passed range.</p>
<div class="highlight-default notranslate"><div class="highlight"><pre><span></span><span class="gp">&gt;&gt;&gt; </span><span class="n">Event</span><span class="o">.</span><span class="n">objects</span><span class="o">.</span><span class="n">filter</span><span class="p">(</span><span class="n">ages__not_gt</span><span class="o">=</span><span class="n">NumericRange</span><span class="p">(</span><span class="mi">3</span><span class="p">,</span> <span class="mi">10</span><span class="p">))</span>
<span class="go">&lt;QuerySet [&lt;Event: Soft play&gt;]&gt;</span>
</pre></div>
</div>
</div>
<div class="section" id="s-adjacent-to">
<span id="s-std:fieldlookup-rangefield.adjacent_to"></span><span id="adjacent-to"></span><span id="std:fieldlookup-rangefield.adjacent_to"></span><h5><code class="docutils literal notranslate"><span class="pre">adjacent_to</span></code><a class="headerlink" href="#adjacent-to" title="Permalink to this headline">¶</a></h5>
<p>The returned ranges share a bound with the passed range.</p>
<div class="highlight-default notranslate"><div class="highlight"><pre><span></span><span class="gp">&gt;&gt;&gt; </span><span class="n">Event</span><span class="o">.</span><span class="n">objects</span><span class="o">.</span><span class="n">filter</span><span class="p">(</span><span class="n">ages__adjacent_to</span><span class="o">=</span><span class="n">NumericRange</span><span class="p">(</span><span class="mi">10</span><span class="p">,</span> <span class="mi">21</span><span class="p">))</span>
<span class="go">&lt;QuerySet [&lt;Event: Soft play&gt;, &lt;Event: Pub trip&gt;]&gt;</span>
</pre></div>
</div>
</div>
</div>
<div class="section" id="s-querying-using-the-bounds">
<span id="querying-using-the-bounds"></span><h4>Querying using the bounds<a class="headerlink" href="#querying-using-the-bounds" title="Permalink to this headline">¶</a></h4>
<p>There are three transforms available for use in queries. You can extract the
lower or upper bound, or query based on emptiness.</p>
<div class="section" id="s-startswith">
<span id="s-std:fieldlookup-rangefield.startswith"></span><span id="startswith"></span><span id="std:fieldlookup-rangefield.startswith"></span><h5><code class="docutils literal notranslate"><span class="pre">startswith</span></code><a class="headerlink" href="#startswith" title="Permalink to this headline">¶</a></h5>
<p>Returned objects have the given lower bound. Can be chained to valid lookups
for the base field.</p>
<div class="highlight-default notranslate"><div class="highlight"><pre><span></span><span class="gp">&gt;&gt;&gt; </span><span class="n">Event</span><span class="o">.</span><span class="n">objects</span><span class="o">.</span><span class="n">filter</span><span class="p">(</span><span class="n">ages__startswith</span><span class="o">=</span><span class="mi">21</span><span class="p">)</span>
<span class="go">&lt;QuerySet [&lt;Event: Pub trip&gt;]&gt;</span>
</pre></div>
</div>
</div>
<div class="section" id="s-endswith">
<span id="s-std:fieldlookup-rangefield.endswith"></span><span id="endswith"></span><span id="std:fieldlookup-rangefield.endswith"></span><h5><code class="docutils literal notranslate"><span class="pre">endswith</span></code><a class="headerlink" href="#endswith" title="Permalink to this headline">¶</a></h5>
<p>Returned objects have the given upper bound. Can be chained to valid lookups
for the base field.</p>
<div class="highlight-default notranslate"><div class="highlight"><pre><span></span><span class="gp">&gt;&gt;&gt; </span><span class="n">Event</span><span class="o">.</span><span class="n">objects</span><span class="o">.</span><span class="n">filter</span><span class="p">(</span><span class="n">ages__endswith</span><span class="o">=</span><span class="mi">10</span><span class="p">)</span>
<span class="go">&lt;QuerySet [&lt;Event: Soft play&gt;]&gt;</span>
</pre></div>
</div>
</div>
<div class="section" id="s-isempty">
<span id="s-std:fieldlookup-rangefield.isempty"></span><span id="isempty"></span><span id="std:fieldlookup-rangefield.isempty"></span><h5><code class="docutils literal notranslate"><span class="pre">isempty</span></code><a class="headerlink" href="#isempty" title="Permalink to this headline">¶</a></h5>
<p>Returned objects are empty ranges. Can be chained to valid lookups for a
<a class="reference internal" href="../../models/fields.html#django.db.models.BooleanField" title="django.db.models.BooleanField"><code class="xref py py-class docutils literal notranslate"><span class="pre">BooleanField</span></code></a>.</p>
<div class="highlight-default notranslate"><div class="highlight"><pre><span></span><span class="gp">&gt;&gt;&gt; </span><span class="n">Event</span><span class="o">.</span><span class="n">objects</span><span class="o">.</span><span class="n">filter</span><span class="p">(</span><span class="n">ages__isempty</span><span class="o">=</span><span class="kc">True</span><span class="p">)</span>
<span class="go">&lt;QuerySet []&gt;</span>
</pre></div>
</div>
</div>
</div>
<div class="section" id="s-defining-your-own-range-types">
<span id="defining-your-own-range-types"></span><h4>Defining your own range types<a class="headerlink" href="#defining-your-own-range-types" title="Permalink to this headline">¶</a></h4>
<p>PostgreSQL allows the definition of custom range types. Django’s model and form
field implementations use base classes below, and psycopg2 provides a
<a class="reference external" href="http://initd.org/psycopg/docs/extras.html#psycopg2.extras.register_range" title="(in Psycopg v2.8)"><code class="xref py py-func docutils literal notranslate"><span class="pre">register_range()</span></code></a> to allow use of custom range
types.</p>
<dl class="class">
<dt id="django.contrib.postgres.fields.RangeField">
<em class="property">class </em><code class="descname">RangeField</code>(<em>**options</em>)<a class="reference internal" href="../../../_modules/django/contrib/postgres/fields/ranges.html#RangeField"><span class="viewcode-link">[source]</span></a><a class="headerlink" href="#django.contrib.postgres.fields.RangeField" title="Permalink to this definition">¶</a></dt>
<dd><p>Base class for model range fields.</p>
<dl class="attribute">
<dt id="django.contrib.postgres.fields.RangeField.base_field">
<code class="descname">base_field</code><a class="headerlink" href="#django.contrib.postgres.fields.RangeField.base_field" title="Permalink to this definition">¶</a></dt>
<dd><p>The model field class to use.</p>
</dd></dl>

<dl class="attribute">
<dt id="django.contrib.postgres.fields.RangeField.range_type">
<code class="descname">range_type</code><a class="headerlink" href="#django.contrib.postgres.fields.RangeField.range_type" title="Permalink to this definition">¶</a></dt>
<dd><p>The psycopg2 range type to use.</p>
</dd></dl>

<dl class="attribute">
<dt id="django.contrib.postgres.fields.RangeField.form_field">
<code class="descname">form_field</code><a class="headerlink" href="#django.contrib.postgres.fields.RangeField.form_field" title="Permalink to this definition">¶</a></dt>
<dd><p>The form field class to use. Should be a subclass of
<a class="reference internal" href="#django.contrib.postgres.fields.django.contrib.postgres.forms.BaseRangeField" title="django.contrib.postgres.fields.django.contrib.postgres.forms.BaseRangeField"><code class="xref py py-class docutils literal notranslate"><span class="pre">django.contrib.postgres.forms.BaseRangeField</span></code></a>.</p>
</dd></dl>

</dd></dl>

<dl class="class">
<dt id="django.contrib.postgres.fields.django.contrib.postgres.forms.BaseRangeField">
<em class="property">class </em><code class="descclassname">django.contrib.postgres.forms.</code><code class="descname">BaseRangeField</code><a class="headerlink" href="#django.contrib.postgres.fields.django.contrib.postgres.forms.BaseRangeField" title="Permalink to this definition">¶</a></dt>
<dd><p>Base class for form range fields.</p>
<dl class="attribute">
<dt id="django.contrib.postgres.fields.django.contrib.postgres.forms.BaseRangeField.base_field">
<code class="descname">base_field</code><a class="headerlink" href="#django.contrib.postgres.fields.django.contrib.postgres.forms.BaseRangeField.base_field" title="Permalink to this definition">¶</a></dt>
<dd><p>The form field to use.</p>
</dd></dl>

<dl class="attribute">
<dt id="django.contrib.postgres.fields.django.contrib.postgres.forms.BaseRangeField.range_type">
<code class="descname">range_type</code><a class="headerlink" href="#django.contrib.postgres.fields.django.contrib.postgres.forms.BaseRangeField.range_type" title="Permalink to this definition">¶</a></dt>
<dd><p>The psycopg2 range type to use.</p>
</dd></dl>

</dd></dl>

</div>
</div>
</div>
</div>


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  <h3><a href="../../../contents.html">Table of Contents</a></h3>
  <ul>
<li><a class="reference internal" href="#">PostgreSQL specific model fields</a><ul>
<li><a class="reference internal" href="#arrayfield"><code class="docutils literal notranslate"><span class="pre">ArrayField</span></code></a><ul>
<li><a class="reference internal" href="#querying-arrayfield">Querying <code class="docutils literal notranslate"><span class="pre">ArrayField</span></code></a><ul>
<li><a class="reference internal" href="#contains"><code class="docutils literal notranslate"><span class="pre">contains</span></code></a></li>
<li><a class="reference internal" href="#contained-by"><code class="docutils literal notranslate"><span class="pre">contained_by</span></code></a></li>
<li><a class="reference internal" href="#overlap"><code class="docutils literal notranslate"><span class="pre">overlap</span></code></a></li>
<li><a class="reference internal" href="#len"><code class="docutils literal notranslate"><span class="pre">len</span></code></a></li>
<li><a class="reference internal" href="#index-transforms">Index transforms</a></li>
<li><a class="reference internal" href="#slice-transforms">Slice transforms</a></li>
</ul>
</li>
<li><a class="reference internal" href="#indexing-arrayfield">Indexing <code class="docutils literal notranslate"><span class="pre">ArrayField</span></code></a></li>
</ul>
</li>
<li><a class="reference internal" href="#citext-fields"><code class="docutils literal notranslate"><span class="pre">CIText</span></code> fields</a></li>
<li><a class="reference internal" href="#hstorefield"><code class="docutils literal notranslate"><span class="pre">HStoreField</span></code></a><ul>
<li><a class="reference internal" href="#querying-hstorefield">Querying <code class="docutils literal notranslate"><span class="pre">HStoreField</span></code></a><ul>
<li><a class="reference internal" href="#key-lookups">Key lookups</a></li>
<li><a class="reference internal" href="#std:fieldlookup-hstorefield.contains"><code class="docutils literal notranslate"><span class="pre">contains</span></code></a></li>
<li><a class="reference internal" href="#std:fieldlookup-hstorefield.contained_by"><code class="docutils literal notranslate"><span class="pre">contained_by</span></code></a></li>
<li><a class="reference internal" href="#has-key"><code class="docutils literal notranslate"><span class="pre">has_key</span></code></a></li>
<li><a class="reference internal" href="#has-any-keys"><code class="docutils literal notranslate"><span class="pre">has_any_keys</span></code></a></li>
<li><a class="reference internal" href="#has-keys"><code class="docutils literal notranslate"><span class="pre">has_keys</span></code></a></li>
<li><a class="reference internal" href="#keys"><code class="docutils literal notranslate"><span class="pre">keys</span></code></a></li>
<li><a class="reference internal" href="#values"><code class="docutils literal notranslate"><span class="pre">values</span></code></a></li>
</ul>
</li>
</ul>
</li>
<li><a class="reference internal" href="#jsonfield"><code class="docutils literal notranslate"><span class="pre">JSONField</span></code></a><ul>
<li><a class="reference internal" href="#querying-jsonfield">Querying <code class="docutils literal notranslate"><span class="pre">JSONField</span></code></a><ul>
<li><a class="reference internal" href="#key-index-and-path-lookups">Key, index, and path lookups</a></li>
<li><a class="reference internal" href="#containment-and-key-operations">Containment and key operations</a></li>
</ul>
</li>
</ul>
</li>
<li><a class="reference internal" href="#range-fields">Range Fields</a><ul>
<li><a class="reference internal" href="#integerrangefield"><code class="docutils literal notranslate"><span class="pre">IntegerRangeField</span></code></a></li>
<li><a class="reference internal" href="#bigintegerrangefield"><code class="docutils literal notranslate"><span class="pre">BigIntegerRangeField</span></code></a></li>
<li><a class="reference internal" href="#floatrangefield"><code class="docutils literal notranslate"><span class="pre">FloatRangeField</span></code></a></li>
<li><a class="reference internal" href="#datetimerangefield"><code class="docutils literal notranslate"><span class="pre">DateTimeRangeField</span></code></a></li>
<li><a class="reference internal" href="#daterangefield"><code class="docutils literal notranslate"><span class="pre">DateRangeField</span></code></a></li>
<li><a class="reference internal" href="#querying-range-fields">Querying Range Fields</a><ul>
<li><a class="reference internal" href="#containment-functions">Containment functions</a><ul>
<li><a class="reference internal" href="#std:fieldlookup-rangefield.contains"><code class="docutils literal notranslate"><span class="pre">contains</span></code></a></li>
<li><a class="reference internal" href="#std:fieldlookup-rangefield.contained_by"><code class="docutils literal notranslate"><span class="pre">contained_by</span></code></a></li>
<li><a class="reference internal" href="#std:fieldlookup-rangefield.overlap"><code class="docutils literal notranslate"><span class="pre">overlap</span></code></a></li>
</ul>
</li>
<li><a class="reference internal" href="#comparison-functions">Comparison functions</a><ul>
<li><a class="reference internal" href="#fully-lt"><code class="docutils literal notranslate"><span class="pre">fully_lt</span></code></a></li>
<li><a class="reference internal" href="#fully-gt"><code class="docutils literal notranslate"><span class="pre">fully_gt</span></code></a></li>
<li><a class="reference internal" href="#not-lt"><code class="docutils literal notranslate"><span class="pre">not_lt</span></code></a></li>
<li><a class="reference internal" href="#not-gt"><code class="docutils literal notranslate"><span class="pre">not_gt</span></code></a></li>
<li><a class="reference internal" href="#adjacent-to"><code class="docutils literal notranslate"><span class="pre">adjacent_to</span></code></a></li>
</ul>
</li>
<li><a class="reference internal" href="#querying-using-the-bounds">Querying using the bounds</a><ul>
<li><a class="reference internal" href="#startswith"><code class="docutils literal notranslate"><span class="pre">startswith</span></code></a></li>
<li><a class="reference internal" href="#endswith"><code class="docutils literal notranslate"><span class="pre">endswith</span></code></a></li>
<li><a class="reference internal" href="#isempty"><code class="docutils literal notranslate"><span class="pre">isempty</span></code></a></li>
</ul>
</li>
<li><a class="reference internal" href="#defining-your-own-range-types">Defining your own range types</a></li>
</ul>
</li>
</ul>
</li>
</ul>
</li>
</ul>

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